Remote control of Android from PC or another Android device Is there a way s.t.:


Whenever SMS with specific keywords are received, that those are then forwarded through SMS to another mobile ?
Or, whenever SMS with specific keywords are received, that those are then forwarded through one's configured gmail account, to another gmail account ?
Whenever the battery of the phone falls below a certain threshold, SMS or email is sent to another mobile ?
One could change settings (such as enable/disable mobile-data or location) for an Android device, remotely by sending it an SMS with certain pattern ?


Of course, when this service is being setup on the target device the device owner explicitly authorizes such change.

The usecase is where the target mobile device (Android phone) is operated by someone who is in the 2nd stage of Alzheimer's disease, stays in another part of the country. The above facility if possible would help providing some remote assistance to the person, and help sort out any issues they may have with banks and other establishments.
Yes this did used to be possible, it is still possible but it requires more on the target device these days.

On below Android 5.0 , it was easy to do what you're saying, however it started to become apparent very quickly that the majority of people did not use this for its intended purpose...

For example, you could previously check on elderly people's movement's around the house to help ensure they're safe... however people would use these features on their partner's to "see" if they're Cheating for example..

It was seen as a serious violation of peoples privacy, and therefore certain measures have been implemented since above Android 4.4.

The new measures are, 
• 1 single SMS application is aloud to recognise OutGoing SMS, Incoming SMS is not restricted because of SMS Verification or ( 2FA ) ..

• Real Time Permission Acceptance

• OnBoot restrictions on some devices

You did used to have Full Control over Android 4.4+ .. You could even have the application hidden with another name and icon, and Only launchable by dialing a phone number.

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Yes you can still bypass everything, but it is very annoying to do..
 .
You would need a permission acceptance screen to accept All permissions on the first start... An OnBoot listener to start the service On Boot... and also you would need to be running as a Device Administrator to Toggle things like Airplane Mode..

The wide selections make the application very obvious to the user, so as long as you are the user on both device's, you should not have any problems.

Using applications like
• SMS Forwarder
• SMS Controller 
• Tasker
and others..

I have attempted building this myself, however it has very limited control.

You can also use this Pre-Built SMS Control App..

It is released under MIT License, so you could modify it to do what you want.

SMS Control - F-droid.org