After some time with my 551 ,I have managed to make it smarter than it was. Launcher Upgrade: -The default launcher is good but I like to flaunt my desktop. ADW Launcher and 91PandaHome were the better ones in my opinion.I had many themes to play with . Explorer App:-I use ASTRO and ANDexplorer ,while ANDexplorer has apk download option on their site,astro looks better and is well known.Both do almost the same thing.Subject to user's choice. Firewall:-DroidWall,Simple interface and it works. Music/Video Player:-Rock Player,It plays almost any format you throw at it.I have tried AAC,RM,FLAC.(ad based apk is available on website) Meridian is also a good music player. Document Viewer:-Samsung bundled a office suite with galaxy 3. However with a phone which could have used the software to it's maximum potential,Galaxy 551,they didn't bundle anything. Documents at go is a free office viewing software (maybe the only one).I haven't tried Think free office lite. For more productivity I would suggest going for a paid office suite at Rs 500 or so ,though I haven't used any. DropBox:-DropBox is free file sharing platform.Couple with a document viewer and you have an office at go.Again good for backup and restore.Available for Windows/Linux/Mac/Android. Ebook Reader:- Playing Angry Birds,Doodle Jump and Fruit Ninja is not feasible everytime considering the extra heat plus high battery usage.A nice way to pass time is reading books.FBReader is my preferred reader ,partly due to it's cross compatibility.Couple it with Project Gutenberg ,it is ideal battery saving passtime. Thats the least I have achieved.I will add more to list in meantime.