SymoLink

Phone app · version 1.1.6

Set up the SymoLink phone and keep it sending

Everything you need to turn an Android phone into your SymoLink gateway: install, permissions for your phone's brand, linking, the SymoLink Box, and what to do when something stops working.

Before you start

What you need

One phone, one job

Use a phone dedicated to SymoLink if you can. A phone that is also someone's personal phone gets restarted, switched to silent battery modes and taken out of range, and each of those stops texts.

Set up the phone

Install, allow, link, check

Do these in order. Step 4 is where most phones need extra care.

Two different numbers

The mobile app password (8 digits) comes from SymoLink and you type it into the app, once, the first time it opens: it lets the app open. The 6-digit code is shown by the app afterwards and you type it into your dashboard: it links the phone to your account. Two numbers, two places.

  1. Download the app

    In the dashboard, open Downloads › Mobile App and scan the QR code with the Android phone. The link in the QR code works for one hour; after that, open Apps again for a fresh one.

    Tap the downloaded file. If Android asks, allow Install unknown apps for your browser (Chrome, Samsung Internet), then tap Install.

  2. Enter the mobile app password (if asked)

    Open SymoLink. If the first screen says Enter the mobile app password, call SymoLink: they read you the password showing right now, 8 digits in two groups of four (like 4821 9135). Type all 8 digits and tap Continue. If your company's password has its company number in front (like 042 · 4821 9135), type the number too: that needs app version 1.2 or newer. It changes every minute and works for one phone only, so type it while you are on the call; setting up a second phone needs the next one.

    This is not the 6-digit code: that comes in step 6. You only do this once per phone; after a reinstall a phone that was linked before is not asked again. If the app does not ask, skip this step.

  3. Open SymoLink and allow what it asks

    On first open the app asks for SMS and Phone. Tap Allow on each. If a popup says the setting is restricted, tap OK and continue with step 4.

  4. Make sure SMS is fully allowed

    Android is strict with SMS for apps installed outside the Play Store, and many phones show SMS as "Allowed" while Send SMS is still blocked. Follow the steps for your phone's brand in Permissions by brand, then come back.

    The app checks this for you. Open Settings › Help › Setup check (app version 1.1.2 or newer; if you don't see it, update the app from the Apps page) (or tap the red Finish setting up this phone card on Home). It lists what is still missing and has a Fix everything button. When Android blocks a prompt, the row changes to Open settings and the screen shows the steps for your phone's brand.

    The dashboard also shows SMS permission missing until it is right.

  5. Let it run in the background

    Phones close apps to save battery. In SymoLink, open Settings › This phone › Battery optimization and allow the app to ignore it. Then do the battery steps for your brand in Permissions by brand.

    Leave Start when the phone turns on switched on (it is on by default).

  6. Link the phone to your account

    The SymoLink Home screen shows a 6-digit code, like 482 915, with a countdown. In the dashboard, open Devices, click Add Device and type the code. If the code runs out, the phone shows a new one by itself. If Devices only shows Request Another Seat, you have no open SMS Gateway seat yet: request one first.

  7. Check that it works

    In the dashboard, open Devices. Your phone should show:

    StatusOnline
    No red badgeNo "SMS permission missing"
    SIM linesEach SIM listed as Ready under Lines
    Last seen"just now"

    Then open ⋯ › Send test SMS on the phone's row and send a text to your own number. When it arrives, the phone is ready.

Permissions by brand

Where each brand hides the switches

Every brand, and sometimes every Android version, puts these in a different place. If a menu name below doesn't match your phone, open Settings, tap the search icon and type the words in bold: SymoLink, restricted, autostart or battery.

The step most people miss

On Android 13 and newer, Allow restricted settings only appears after you have tried to turn on SMS once and been blocked. So: try SMS first, see the "Restricted setting" popup, then go back to App info and open the ⋮ menu.

BrandAllow SMS fullyKeep it running
Samsung Settings › Apps › SymoLink › Permissions › SMS → Allow. If blocked: back to App info → ⋮ → Allow restricted settings → SMS → Allow again. Samsung may show "SMS: Allowed" while Send SMS is still off; trust the dashboard badge. App info › Battery → Unrestricted. Also Settings › Battery › Background usage limits: make sure SymoLink is not in Sleeping or Deep sleeping apps.
Xiaomi, Redmi, POCO App info › Permissions → SMS → Allow. Then App info › Other permissions and allow Send SMS and Service SMS. These are separate on Xiaomi and are the usual reason texts do not go out. App info › Autostart → on. App info › Battery saver → No restrictions. Lock the app in Recent apps (drag down on its card or tap the lock).
OPPO, realme App info › Permissions → SMS → Allow. If it asks, confirm Allow sending SMS. Use ⋮ → Allow restricted settings if SMS is greyed out. App info › Battery usage: allow background activity and Allow auto launch. Lock the app in Recent apps.
vivo App info › Permissions → SMS → Allow, including Send SMS if listed separately. Use ⋮ → Allow restricted settings if blocked. Settings › Battery › Background power consumption → allow SymoLink. Turn on Autostart for it (in iManager or Settings search "autostart").
Infinix, Tecno, itel App info › Permissions → SMS → Allow. Use ⋮ → Allow restricted settings if blocked. Phone Master or Settings search "auto-start" → allow SymoLink. App info › Battery → no restriction. Lock it in Recent apps.
Google Pixel, Motorola, Nokia App info › Permissions → SMS → Allow. If "Restricted setting": App info → ⋮ → Allow restricted settings → try again. App info › App battery usage → Unrestricted.

After changing any of these, open SymoLink once. The dashboard badge clears within about a minute. If it doesn’t, see Still blocked?.

SymoLink Box

Add the box for calls

The box connects to Wi-Fi and uses the phone over Bluetooth to place and take calls. The phone must be linked (step 6) first. Your company must also have assigned the box to your account, and you need an open Call Gateway seat (ask with Request Another Seat on Devices).

  1. Power the box

    Use the power adapter and cable that came with the box, straight into a wall socket (not a laptop USB port). The first start takes up to 5 minutes: don't unplug it while it prepares itself. Keep the phone within a few steps of the box.

  2. Start setup on the phone

    In SymoLink, tap Set up a gateway box on Home (or Settings › SymoLink Box). Turn on Bluetooth and allow Nearby devices when asked.

  3. Pick the box and your Wi-Fi

    Tap the box in the list. Its name is SymoLink- plus the last four characters of the Box ID on its label (for example SymoLink-WQNF). The app fills in the box's setup code by itself. If it asks for one, open Devices in the dashboard, click Add SymoLink Box, then Show code. Then choose your Wi-Fi and type its password. The box connects and joins your account. Set the box up from the phone it will call through: SymoLink records that phone’s number on the box’s calls (you can change it later on the box’s page in Devices).

  4. Check it

    In the dashboard Devices, the box shows Online and its phone link says Connected.

This is normal

The phone's Bluetooth settings show the box as "Connected for calls". That is how the box uses the phone's SIM for calls. Don't disconnect or unpair it.

Wi-Fi

The box only joins 2.4 GHz Wi-Fi and has a small antenna. Keep it near the router or mesh node. If your router shows separate 2.4 GHz and 5 GHz names, choose the 2.4 GHz one.

Updating the app

Install a new version without linking again

An update goes on top of the app you have. The phone keeps its link, name, SIM lines and permissions, so there is nothing to redo in the dashboard.

  1. Check which version you have

    In SymoLink, open Settings › Account. App version is at the bottom, for example 1.1.3 (5). The dashboard shows it too, on the phone's page in Devices.

  2. Download the new version

    In the dashboard, open Downloads › Mobile App and scan the QR code with the phone. It always gives the newest version. The link works for one hour.

  3. Tap Update. Don't uninstall.

    Open the downloaded file and tap Update (some phones say Install). Do not uninstall the old app first, and don't clear its data. If Google Play Protect warns you, tap More details, then Install anyway.

  4. Check it

    Open SymoLink. Settings › Account shows the new version, and in the dashboard the phone is still Online with the same name. That's it.

If it asks for a 6-digit code

That means the old app was removed before the new one went on (uninstalled, or its data cleared). Enter the code in Devices › Add device as usual. From version 1.1.3, SymoLink recognises it is the same phone and replaces the old entry by itself: the name, SIM lines and preferred line carry over, and nothing is left to clean up.

The same phone shows twice in Devices

This can happen once if the phone was reinstalled while it had version 1.1.2 or older. Find the old entry (it shows Offline and an older version), open ⋯ on its row and choose Delete. One step: its duplicate SIM lines disappear with it, and message history stays. Then check the preferred line in Cellular Lines.

Everyday use

Reading the phone and changing things

The banner on Home

Banner saysWhat it meansWhat to do
All systems onlineInternet works and SymoLink answered recently.Nothing.
Starting…The app is starting its connection.Wait a few seconds, or tap the banner to try again.
No internet connectionThe phone has no Wi-Fi or data.Fix Wi-Fi or mobile data. Texts wait safely in SymoLink.
Cannot reach SymoLink CloudInternet works but SymoLink isn't answering.Tap the banner to try now. The phone also keeps trying by itself. See troubleshooting if it lasts over 10 minutes.
Sending is pausedSomeone turned on Pause sending.Turn it off in Settings › This phone.

Common changes

Advanced settings

Settings › Help › Advanced holds the server address and logs. Only change them if support asks. The server address must be https://api.symolink.com/mobile/v1; Reset server address puts it back.

Troubleshooting

Something stopped working

Find what you see, then follow the fix from the top. Most problems are one of three things: a permission, battery saving, or the internet.

The app asks for a mobile app password, or won't take it

SymoLink lets a new phone in only with the password it reads out to you. It is not the 6-digit code.

  • Call SymoLink and ask for the password showing now; type it straight away. It changes every minute.
  • "Not right": it probably changed while you typed. Ask for the current one.
  • Your company's password has a number in front and the app won't take that many digits: update the app to version 1.2 or newer.
  • "This phone was set up with another company's mobile app password" on your dashboard when you link it: reinstall the app, type your own company's password, then link it with the new 6-digit code.
  • "Just used for another phone": each password works for one phone. Wait for the next one (under a minute).
  • "Too many wrong passwords": wait the minutes shown, then try again with a fresh password.
  • "No internet": the app checks the password with SymoLink. Connect to Wi-Fi or mobile data and tap Try again.
Dashboard says "SMS permission missing"

Android has not fully allowed Send SMS and Receive SMS. The phone can't send or receive texts.

  • On the phone, open Settings › Help › Setup check. It names exactly which permission is blocked (for example "Send SMS") and opens the right settings screen.
  • Follow your brand's row in Permissions by brand, including Allow restricted settings.
  • Turn SMS off and back on in the app's permissions, then force stop the app and open it again.
  • Xiaomi, Redmi, POCO: also allow Send SMS and Service SMS under Other permissions.
  • Still there after a minute? See Still blocked? below.
Phone shows Offline in the dashboard

The phone hasn't checked in for a few minutes.

  • Look at the phone. Is it on, charged, and does the SymoLink banner say "No internet"? Fix the Wi-Fi or data.
  • Open the SymoLink app once. If the phone killed it to save battery, this restarts it. Then do your brand's battery steps so it doesn't happen again.
  • Check Settings › This phone: Pause sending must be off.
  • After a restart, if it stays offline: make sure Start when the phone turns on is on and battery is unrestricted.
Banner says "Cannot reach SymoLink Cloud" even with internet

The phone reaches the internet but not SymoLink.

  • Tap the banner to try now.
  • Check Settings › Help › Advanced › Server address. It must be https://api.symolink.com/mobile/v1. If not, tap Reset server address.
  • Some public or office Wi-Fi blocks apps. Switch the phone to mobile data to test.
  • If every phone is affected at once, SymoLink itself may be down. Contact your SymoLink support. Texts wait in SymoLink and go out when phones reconnect.
Texts stay "Waiting" or fail

The phone received the text but can't send it, or hasn't received it yet.

  • Phone offline or paused? Fix that first (see above).
  • Check the SMS permission badge and your brand's Send SMS switch.
  • Check the SIM has load and signal. Try sending a normal text from the phone's own Messages app.
  • Check the SIM chosen in Settings › Sending › Sending rules, and the sending hours.
  • Many texts at once? The wait between texts spaces them out on purpose so carriers don't block the SIM.
Replies from customers don't show up

The phone isn't passing incoming texts to SymoLink.

  • Receive SMS must be allowed (same steps as the SMS badge).
  • Turn on Settings › Help › Advanced › Double-check incoming texts. It catches texts some phones don't report.
  • Don't set SymoLink as the phone's default SMS app, and don't let a "junk" filter block the sender.
SIM lines are missing, or listed twice
  • Missing: allow the Phone permission. SIM lines appear within a minute.
  • Listed twice: the same phone has an old entry from before a reinstall. In Devices, choose ⋯ › Delete on the old entry (Offline, older version) and its lines go with it. From app 1.1.3 this is done automatically.
"App not installed" when installing
  • An older SymoLink build is on the phone with a different signature. Uninstall it, install the new one, then link again with the new 6-digit code. After that, updates install over the top.
  • Make sure the download finished. Download it again from Downloads › Mobile App.
  • Low storage can also cause this. Free some space.
Download link says it has expired

Links work for one hour. Open Downloads › Mobile App in the dashboard again for a fresh QR code.

The 6-digit code doesn't work
  • Use the code on screen now. Codes renew; an older one stops working.
  • Too many wrong tries locks that code. Tap Refresh code on the phone.
  • Make sure you're signed in to the right client account in the dashboard.
  • The dashboard says "No SMS Gateway seat yet" or "All … SMS Gateway seats are in use": use Request Another Seat on Devices, or delete a phone you no longer use.
Phone says it was deactivated

Someone deactivated it in the dashboard. Tap Re-activate on the phone and enter the new code in Devices › Add device.

Box setup can't find the box
  • Bluetooth on, Nearby devices allowed for SymoLink, phone close to the box.
  • A box that is already linked and online doesn't show in the list. A new box, or one removed from Devices, shows even while it is online. So does a box that has had no Wi-Fi for about 3 minutes. To change its Wi-Fi, take it where its old Wi-Fi isn't available (or turn that Wi-Fi off), wait about 3 minutes, then search again.
  • Unplug the box, plug it back in, wait a minute, then tap Search again.
Box is offline, or calls don't connect
  • Box power: use the power adapter and cable that came with the box, straight into a wall socket. Weak chargers and laptop USB ports make it restart.
  • Wi-Fi: 2.4 GHz only, near the router. If your Wi-Fi password changed, run box setup again.
  • In the phone's Bluetooth settings the box should show "Connected for calls". If not, keep the phone near the box and wait a minute.
  • The SymoLink phone must be online too, because calls use its SIM.
Battery drains or the phone gets hot

Keep it on a charger, out of direct sun, with the screen off. The dashboard marks a phone at 20% or less as Low battery, and a nearly empty phone may close the app.

Still blocked?

When the phone won't let SymoLink send texts

Some phones refuse to switch on texting for apps that didn't come from the Play Store, even after you tap Allow. It isn't your fault and nothing is broken. A computer connected to the phone with a USB cable can switch it on directly. It's a one-time fix: afterwards the phone works normally, and future app updates keep the setting.

Easiest

Ask support to do it

Contact your SymoLink support and say: "My phone still shows SMS permission missing after Setup check. Please do the USB fix." Have the phone and its USB cable with you. It takes about 5 minutes.

Do it yourself

Use a computer and a cable

Good for someone who is comfortable installing a program and copying one line of text into it. Open the steps below.

Show the steps
You'll need
  • A Mac or Windows computer, and the phone's USB cable.
  • A free tool from Google called Platform Tools. Get it from Google's download page (choose Mac or Windows) and unzip it. You'll get a folder called platform-tools.

  1. Unlock the phone's "developer" setting

    On the phone, open Settings, tap the search icon and type Build number. Open it and tap Build number 7 times, until the phone says developer mode is on.

    Search again for USB debugging and switch it on. This lets the computer talk to the phone.

  2. Connect the phone to the computer

    Plug in the cable. The phone asks "Allow USB debugging?". Tap Allow. No question? Unplug the cable and plug it in again.

  3. Open the typing window in the platform-tools folder

    • Windows: open the platform-tools folder. Click the bar at the top that shows the folder's location, type cmd and press Enter. A black window opens.
    • Mac: right-click (or Control-click) the platform-tools folder and choose Services › New Terminal at Folder (on some Macs it is directly in the menu). A window opens.

  4. Paste one line and press Enter

    Click Copy, click inside the window, paste (Windows: right-click; Mac: ⌘ V), then press Enter.

    Windows: paste this line
    adb shell "pm grant com.symolink.gateway android.permission.SEND_SMS; pm grant com.symolink.gateway android.permission.RECEIVE_SMS; pm grant com.symolink.gateway android.permission.READ_SMS; appops set com.symolink.gateway SEND_SMS allow"
    Mac: paste this line (it starts with ./)
    ./adb shell "pm grant com.symolink.gateway android.permission.SEND_SMS; pm grant com.symolink.gateway android.permission.RECEIVE_SMS; pm grant com.symolink.gateway android.permission.READ_SMS; appops set com.symolink.gateway SEND_SMS allow"

    If nothing appears, it worked. The window simply waits for more typing.

  5. Check on the phone

    Open SymoLink and go to Settings › Help › Setup check. Send and receive texts should say Done. In the dashboard, the red "SMS permission missing" label disappears within a minute.

    Unplug the phone. You can switch USB debugging off again; SymoLink keeps the permission.

If you see a message instead
  • "no devices": the phone isn't connected or USB debugging is off. Repeat steps 1 and 2.
  • "unauthorized": look at the phone and tap Allow, then paste the line again.
  • "not recognized" or "command not found": the window wasn't opened in the platform-tools folder. Repeat step 3.
  • "Unknown package": SymoLink isn't installed on this phone.