Hi, my 1st Windows Phone is the 710. Recently I got myself a 620 but I'm still mostly using my 710 daily. I don't really use a lot of apps or play a lot of games on my phone so I can't really recommend the best ones but I can show you what I have on my phone at the moment. Maybe you should explain the type of apps that you're looking for or the type of games that you like to play so we can provide better recommendations. The following is what I have on my phone at this moment.
Social Networking :
- Facebook (official app)
- Twitter (official app)
- Mehdoh (3rd party app for Twitter)
- Blueprints (3rd party app for Tumblr)
- Disqus (official app)
Apps for Sites:
- WPCentral
- Paypal (official)
- Brit & Co.
Music + Videos:
- MetroTube (3rd party app for YouTube)
- Vimeo (official app)
- Beem Plus
- Nokia Music
- Vevo
Photos:
- Fhotoroom
- Creative Studio
- Camera Extras
- PhotoBeamer
Communication:
- Skype (official app)
- Viber (official app)
- Talkbox (official app)
Navigation:
- Nokia City Lens
- Nokia Transport
- Nokia Drive
- Nokia Maps
Utilities / Others:
- Shazam
- Nokia Play To
- Flashlight-X
- Adobe Reader
- Xbox Extras
- Xbox Smartglass
You can also look through all the previous app and game reviews on WPCentral using the following links but since your phone is running the Windows Phone 7 operating system, you can only download Windows Phone 7.x apps and games only. You cannot use any app that is specifically indicated as only for Windows Phone 8.
Apps | Windows Phone Central
Games | Windows Phone Central
Also make sure that you have updated your phone OS to the latest version.
The following is my current Windows Phone OS and Nokia firmware version on my 710.
OS version: 7.10.8862.144
Firmware revision number: 1600.3036.8853.12440
Any more things you like to know, feel free to ask or message me directly.
Enjoy your Windows phone!