well you'd want a weather app because, well everything has a weather app these days XD : Amazing Weather HD
for quick dialing and a premium dialing experience, try RapDialer Paid
for the best news and RSS app in the marketplace: Weave News Reader
and of course since you're posting on this site: WPCentral
since everyone has one: Facebook Beta. needs a special link for this one here:
Facebook Beta | Windows Phone Apps+Games Store (United States)
the best photography app of all time: ProShot
and for everything else that maybe useful: Jack of all Tools
you should also check out the nokia collection in the store
enjoy!
PS: I just realize that with only a 5MP camera you might not need proshot, but it's a great app.
update: forgot that u said tips and tricks as well:
Tips and tricks | Windows Phone 8 | Windows Phone How-to | Windows Phone (United States)
http://forums.windowscentral.com/windows-phone-8/204483-wp8-newbie-tips.html
one trick that is extremely useful is that say if u want to type one symbol or a number, instead of having to tap the 123... key, press desired key, then tap abc... to get back, simply press 123 and hold, you'll see the keyboard change, without removing your finger, drag it to the desired key, release touch and you'll have your qwerty keyboard back
try it it's neat