Resenderrealme: SMS forwarding stops when the screen is off
realme UI is ColorOS under another name, and it treats background apps the same way: frozen unless you say otherwise. Two switches let Resender keep forwarding with the screen off.
The two switches
- Open Settings → Apps → Resender → Battery usage.
- Turn on “Allow background activity”.
- On some phones, also turn on “Allow auto launch” (Settings → Apps → Auto launch; on older versions Settings → Battery → App auto-launch).
- Allow background activity. Settings → Apps → Resender → Battery usage: allow background activity (also called Allow background running or Unrestricted, depending on the version). On ColorOS 16 the same screen offers three choices instead of a switch — Allow background activity, Smart mode (Recommended), Restrict background activity: choose the first; on ColorOS 15 the Optimize battery use line below switches to Don't optimize by itself once background activity is allowed.
- Allow auto launch. Settings → Apps → Auto launch on newer versions, Settings → Battery → App auto-launch or Settings → App management → Resender → Auto launch on older ones: switch Resender on, so the system starts it after a restart or when an SMS arrives while it is not running.
Then take Resender off Android's own battery optimisation: the app's main screen has a button that opens the system list — find Resender and choose Don't optimize. ColorOS also has a list of its own: Settings → Battery → Advanced settings → Optimize battery use — set Resender to Don't optimize there; the default is Always ask.
How to check it worked
Lock the phone, wait a minute, and send it an SMS from another phone. The email should arrive within seconds. If it arrives only after you unlock the phone or open the app, one of the switches is off — after a system update, check both again.
What no app can do
realme UI's battery screens have no public interface. No app can read them, change them, or tell whether you have set them. Resender shows a red line when Android reports that it is being restricted and opens the right system screen for you — the switches are yours. Skip them, and messages arrive late or not at all while the app has done everything it is allowed to do.
Questions
Forwarding works while the app is open and stops when I lock the phone. Why?
realme UI freezes apps that are not on screen unless they are allowed background activity and auto-launch. Resender receives the SMS only when the system lets it run again. Set the two switches on this page once.
Where is Auto launch on realme UI?
Settings → Apps → Auto launch on the newest versions; Settings → Battery → App auto-launch or Settings → App management → Resender → Auto launch on older ones; or inside the Phone Manager app under Privacy permissions → Startup manager.
Is the Android battery-optimisation switch also needed?
Yes. Resender's main screen has a button that opens the system list: find Resender and choose Don't optimize.
Why doesn't Resender switch these settings itself?
realme UI's screens have no public interface: no app can read or change them. The one Android setting an app could change with a single dialog needs a permission Google Play grants only to alarms, calling and similar categories, which a message forwarder is not.
Is this the same as OPPO?
Yes. realme UI is built on OPPO's ColorOS, so the switches are the same and only the menu names differ.