Apple has raised the filesize limit on App Store downloads over 3G and 4G to 100MB, reports say. Previously the cap was 50MB, presumably to ensure a good user experience and appease cellular carriers. Prior to the launch of the third-generation iPad in March 2012, the cap was just 20MB.
Increasing the limit
to 100MB may be a concession to two factors. Even small-scale apps are now regularly exceeding 50MB, thanks to Retina graphics and universal iPhone/iPad binaries. That could be exacerbated as developers start folding 64-bit support into apps for the sake of the iPhone 5s and fifth-gen iPad.
Developers, meanwhile, often try to keep apps under Apple's limit to encourage downloads. If an impulse purchase is blocked while a person is on cellular data, they may simply skip buying it entirely, even when back on Wi-Fi.