What were the notifications? Pop-ups? I've never seen that. It could be malware just pushing an app.
I suggest that you change your Google password to something new immediately and enable 2-factor authentication, in case anyone has access to your account. A factory reset would also be a good idea to get rid of any malware or tracking software. It will erase any data on the device, so make sure you have any photos backed up, then go into your settings (probably SETTINGS>BACKUP & RESET, but it might be under SECURITY depending on your phone and version of Android) and perform a factory reset.
Well I know my phone is being tracked which I really dont care but whats bothering me is its being hacked and someone is simply syncing all my personal and professional datas, photos, vdo's etc.. even after using the factory reset option everytime tht person somehow manage to continue the same max in 2-3day. How do I find whos doing it and how do I stop it or get details of everything tht gets shared/transferred. The hand set I use is Nokia XL which operates on android.
What kind of phone do you have? That would help me to figure out what tools they may be using to follow you. Different phone operating systems (IOS, Android, Windows Phone 7, Symbian) have different exploits.