Unfortunately, at this time, there is a known issue with the images enlarging within the eBay app on Android devices. Our engineers are aware of this issue and at this time the issue appears to be within the eBay app itself as the supersize feature operates correctly if you visit eBay on the browser of your device. The feature also operates as intended elsewhere.
I will update this thread as soon as more information regarding this issue becomes available.
Apologies for any inconvenience this may cause.