Apple has quietly increased the maximum app size downloadable over AT&T’s 3G network to 20MB over its previous 12MB cap. The increase also applies to over the air iTunes downloads and other international territories as users in Germany and Canada are also confirming the increased download limits are in effect on other carriers.
Apple previously limited iTunes music and application downloads over 3G networks to downloads smaller than 12 MB in order to cooperate with carriers in maintaining the stability of 3G data networks.
Will this phone able to download 30 mb ?
Apps that are 30 MB require a Wi-Fi connection to download, or can be installed via iTunes. You can download more than 30 MB, what app designers usually do is have files download after the app is installed. Email attachments, etc also work when over 30 MB.