Deleting Android messages manually ? i think this idea is bad ,In order to make sure your text messages deleted on Android, it is necessary for you to use
Data Cleaner software, after all, the Data Cleaner software can delete or erase everything on Android phone ,besides delete all messages, there is another alternative way to destory the data on the phone. The principle is that first write a set of random digits to the phone, then factory reset. This data on the phone will be overwritten and it is more secure.