Sometime this week, Apple and the Canadian wireless carriers increased the 3G file size limit for App Store downloads up to 20MB.
Previously, when users were connected to 3G, they could only download apps that were up to 10MB in size. Anything greater than 10MB needed a WiFi connection.
The new limit is now 20MB and anything greater than 20MB will need WiFi.
However, unless you have the Rogers/Fido 6GB data plan, we recommend to always download apps on WiFi. The Canadian wireless carriers do not provide very much data and you don’t want to be using it up downloading apps when you can use WiFi.