App Trial Period
Apple should really consider giving developers the functionality to provide trial versions of their software to users. From a development standpoint, there will be next to zero (if any) changes done on your part. A developer could simply mark a paid for application as "tryable". After that, a user could download a trial version of that software (via a button next to the "Buy ($$$)") and the software will be downloaded. After the trial period is up (determined by the developer) the application will no longer function.
I see absolutely no cons to this whatsoever. Not only will it be beneficial to the user, but to Apple and developers alike. Users may be likely to make more purchases from the app store if they could try the application before they purchased it. Up until now, this could be done by the developer making a "Lite" version of their application. Not only does this waste the developers time (making, updating, and maintaining multiple versions of their software) but Apple's as well (more applications must go through the already slow and broken verification process). It would also mean higher product reviews for some applications. Most of the time I see reviews on an application that are very low, they're all because the user thought their first gen iPod touch had a camera and a GPS and they're angry because the app they just paid for doesn't work at all (do to missing and incompatible hardware). Had they been able to download a trial version, they could find out (before they buy) that the application is unsupported by their device, thus saving the developer a review from someone who couldn't read "NOT SUPPORTED BY 1st GEN iPod TOUCHES!" at the beginning of the description.
Also, if and when this feature does come out (I'm sure its been suggested before), please do not say this is a "revolutionary" feature.
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