That'll teach me to buy a phone off Lazada. Interesting - a friend of mine (more techy than I am) also recommended LineageOS a year or so ago, but I wasn't (and still am not) experienced enough with Android to try to install a different OS, although I once did download and install a genuine version of the OnePlus2 O/S after I found built-in malware in my phone after I installed MalwareBytes. Instead, they have brought out new phones - OnePlus 3, 4, 5, 6, 7, 8 - which naturally peed off most OnePlus 2 owners. I did investigate upgrading the OS, but my phone is a OnePlus 2 and the manufacturers have not updated the OS for it. If anyone can recommend an app that does a similar job to Bitdefender, but without the impact on performance, I'd give it a try. I guess Bitdefender was doing a very thorough job of scanning all my data - and very often - but I'd rather have a responsive phone.

Then I got a reminder for my Bitdefender Mobile Security app yearly subscription and decided to uninstall it to see if that made a difference. It got so bad that I came very close to buying a new phone. I set to 'On' the 'Developer options' so that I could monitor the CPU usage and saw that it was getting to 20, 30 even 40 while it was very slow, but down to 7 or 8 when working normally. I tried to find an app that would tell me what was using all the CPU time, but couldn't find any useful ones that worked on Android 6. It would also stop responding for 10 to 30 seconds at any time for no apparent reason. For several months - maybe 6 or more - my old Android 6 phone had been running incredibly slowly after I first woke it up by touching the finger sensor.

Bitdefender find my phone