Re: my one plus one battery is not charging 100%
Is the phone or battery new? Apparently, lithium batteries have to be calibrated during the first couple of uses for optimal performance.
Also, did you update the phone's software recently?
Re: unable to access "securities". it says " unfortunately,settings has stopped"
Had this issue a while ago, too. Try going to the app drawer and holding on settings app icon, opening its app info, and clearing data.
Re: accidentally set videos to always open in youtube
Go to settings - Enter your apps menu - Find the app you made default and open it - Press "Clear defaults"
Had the same problem, turned out that the power button was getting stuck. Was able to re-position it without opening the phone, but not sure how safe that is to do)
Re: Samsung s3
Well, I've been using my S3 for almost 3 years now, and still see no reason to update. Will probably use it for another year at least, unless it dies on me.
So far Google analytics seems to be the best tool. Both App Annie and the Google Play built in analytics seem to be quite sluggish on updating stats. Plus, the live monitoring on GA is very convenient, too.