Mobile App Size
Arsenal's mobile apps are well under 100 MB (approximately 40 MB for iOS).
Image Cache Size
Arsenal's app temporarily stores several versions of recently taken or viewed photos on your phone. This makes it possible to quickly scroll through photo thumbnails and zoom in to see full resolution without waiting for each photo to transfer.
Arsenal stores these images in a temporary cache that is managed by your phone's operating system. When that space is needed by another app, your phone will automatically take the space back. You do not need to manually empty the cache or worry about Arsenal "filling up" your device.
As you may have guessed, having more free space on your phone will improve Arsenal's photo review performance. When more space is available, Arsenal can temporarily store more preview images so they're available for you.
Arsenal device software/firmware update size
When there is a software/firmware update for your Arsenal device, the app will download and temporarily store the file before transferring it to your Arsenal device.
Once the software/firmware update has transferred, the Arsenal app will delete it to free up that space on your phone.