It is not 100% safe, that is the reason why avast flags it as a PUP.
The only issue is that the makers of TR and many users don’t understand what a PUP is.
Paid or not doesn’t matter.
Paid applications can also be dangerous.

Quote from Denics (avast team):

The detection will remain for security reasons, that is the final statement.

The application could be used for stealing sensitive information. Every notification can be turned off, that’s an android feature since 4.3 so Total Recall could be running stealthily on a phone without user’s consciousness. Also, the application can be decompiled, modified and repacked by a 3rd party to disable its notifications.

avast! Mobile Security offers the option to disable PUP detection or add an application to a whitelist so it will no longer be detected on the device.