One of the novelties that iOS 7 has brought and that may have gone unnoticed is that the limit to download applications over 3G or LTE network has increased to 100MB. Previously, the limit was set at 50MB and although sufficient in most cases, it could always be the case that we tried to download an application that would occupy 51MB.
With each version of iOS, Apple the limit has been increasing to be able to download applications without Wi-Fi connectivity. In 2008, the limit was 10MB and clearly it was more than insufficient. With the proliferation of 3G networks and the arrival of the Retina Display, Apple decided to relax this measure that had the sole purpose of avoiding exhausting our data rate.
Little by little the applications have been occupying more but we have also gained in download speed, therefore, having a Wi-Fi network has not become an essential requirement Except in very specific cases like in the case of Infinity Blade, to name an example.
You already know, from iOS 7 you can download applications that occupy 100MB of space or less via 3G or LTE. If it exceeds that size, you will need to connect to a Wi-Fi network.
More information - Apple could allow downloading old versions of apps from the App Store
Source - 9to5Mac
I would swear that the limit at the beginning was 20mb ...
Excellent!!! They should put it unlimited, and that everyone take care of their data ^^^^