The Google platform accounted for 381m of them.
The data and infographics come from madvertise's latest 'madreport'. The European mobile ad firm partnered app search specialist, Xyologic for the research, which covers download trends across the UK, Germany, France, Spain and Italy - the EU5.
iPhone and Android app downloads across the EU5 reached 603 million in Q1, rising from 552 million in Q4.
Android was the star of the show, growing from 262 million to 381 million between Q4 and Q1, while iPhone fell from 290 million to 222 million.
In fact, Android was the leader for app downloads across all countries, and the firm's claim the Google OS is the best way for developers to get their apps noticed.
Check out the infographics below to see what apps the UK favoured during Q1.