Apple has the most number of application for its phone till now but if you see at which rate android is covering the market today ,you can predict the future for the android phones and its applications! After these two big companies comes the blackberry phones but looking at business of the Nokia phones and windows it can be predicted that windows 7.5 phones will also surpass the blackberry phones!
The quality of the application will also matter a most! If you will see the history then it appears that apple always provides new version of its application for its phone, so that is why they have the better quality of applications! Now android seems to be reaching near iphone and it will be interesting to see how others will react to it!