To put some numbers on it, according to this research (http://blog.appannie.com/app-annie-index-market-q1-2014/), relative app revenue numbers have been something like:

    Q2 2013: Apple +230%
    Q3 2013: Apple +210%
    Q4 2013: Apple +110%
    Q1 2014: Apple +85%

Android's market share (especially in emerging markets) is exploding (https://s3.amazonaws.com/files.appannie.com/reports/App+Anni...), while Apple's app store revenue are substantially flatter (http://images.apple.com/nl/pr/pdf/q2fy14datasum.pdf).

Apple's definitely on top right now, but the gap is narrowing very, very quickly.