im having a problem with my iPhone

Sometimes when im running an application it will stop what im doing and send me straight to the main screen.
This happens when im using YouTube, Safari, Google Maps, and MobileChat

would anyone know what is going wrong with my phone?




I'm guessing it's a package that i installed using Installer.app?
These are the current packages i have installed:
Dictionaries: CMUDICT, Gazetter2k-zips, Merriam-Webster, Oxford Collocations, Thesaurus-ee,
Games: 4Balls, iSolitaire, iZoo, Marble, NES, snes4iphone, SuperPong, T4Two, Tris
Network: Stumbler, SwirlyMMS
Productivity: Mobile Finder, MobilePreview, MobileToDoList2, Sketches, weDict
Sources: Community Sources
System: BSD Subsystem, Categories, Installer, OpenSSH, SummerBoard, Term-vt100
Themes (SummerBoard): Buuf2, Japanese, SNES Zelda, Xadacka's Random Red
Tweaks(1.1.3): IM Chat 1.1.3 Fix, T-Mobile 1.1.3 Tzones, TMobile Carrier Logo
Tweaks (1.1.4): Youtube Activator 1.1.4
twenty08:MobileChat
Utilities: Converter, Services