The main ones that I use mith are (all from Android App Store unless otherwise stated):
ES File Explorer (Free, does what it says)
Titanium Backup (Free version, backs up all your apps/settings, requires root)
SMS Backup+ (Free, backs up SMS and call log to gmail account)
Barcode Scanner (Free, for scanning QR codes)
Adfree Android (Free, edits hosts file with lots of ad sites so that they don't appear, requires root)
ESPN ScoreCentre (Free, gives football/F1/Tennis etc. scores, can add favourite team etc. to easily see your teams scores)
BetterBatteryStats (Free from
XDA, shows all wakelocks to find out what's draining your battery)
GMail (Free, access to GMail accounts, has push email support)
Opera Mobile (Free, better than the stock browser)
Amazon App Store (Free from
Amazons site, requires a US account can be made with
following this guide, get their "Free App Of The Day" each day, can't buy things here due to needing an American CC)
Edit - Oh, I use SwiftKey X as a keyboard too, you have to pay for it though, I got it free from Amazon App Of The Day though

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Edit again - SwiftKey X is free on GetJar.com

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