Hmm considering you just bought it, I wouldn't recommend my solution 2 but it could do the trick.
Solution 1:
-Download backup software.
-Backup
-Do a factory reset
-Reload all apps except browser (both app and data)
See if it worked. If not:
Solution 2:
-Install Titanium Backup
-Backup ur shit
-Download Clockwork mod and Superuser. Install.
-Download Custom Rom of your choice (google your phone and add rom after it, should find loads of results)
-Root Phone and Install Custom Rom
Try if the apps work. If not:
-Since Phone is rooted, you can install an app that diagnoses and fixes phone stuff
-Run software of choice
Try if apps work. If not:
I dont know what to do.