Really strange battery issue?

Question

So, I don't have a picture, but my Android phones batter is on the fritz. At first it just started draining quickly so i checked if I had any apps that where draining it quickly but I didn't have anything out of the normal, the highest thing that was draining it was the Android systems which was 6%. I didn't think much off it since it is an older model and was thinking maybe the battery was just getting old and draining quicker. I just put it on the charger and brought it up to 100%. I took it off the charger and started watching YouTube which I knew drained it quickly but then something weird started happening. It went from 100% and instantly dropped to 1%. Thinking it was just a glitch I turned off the screen then turned it back on and it was at 90%. I went back to watching YouTube. Next thing I knew I looked back at the battery and it said 24%. I was confused and so i started to watch the battery, it drained normally for about a minute then started changing like this 58%,20%, 80%, 1%, 100%, and just all over, its been doing this for about three days now and I'm honestly not sure what's going on. I'm wondering if there something wrong with my battery or if this is just some strange phone glitch?

Answer 1

Go to Settings>Developer Options>Running Services and check to see if something you don't recognize is using a bunch of processing power.

If yes, you've probably got a virus.

Otherwise, a factory reset could fix the issue.