Currently there is no video length requirement when recording from an iOS device when recording from the Sibme iOS app. However, you are limited to the amount of storage space you have on your iOS device. The Sibme iOS app allows a user to record in three different resolutions: low - 360p, medium - 480p, and high - 720p. This table gives you a rough idea of how large video files can get when recorded in low, medium, and high resolution. The Sibme iOS app does reveal on the record screen how much time you have available to record in the resolution you have enabled. 

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