Small changes, big impact
Leaked image of the Z Flip 4 shows a barely visible crease

Galaxy Z Flip 4 may come with thinner hinge
At first glance, the cover screen appears to be the same size, but Mr_TechTalkTV says it’s grown a bit. Rumor has it that the size will increase from 1.9 inches to 2.1 inches.
The position of the physical fingerprint sensor has not changed and it is still on the right side, integrated into the lock button. The camera layout as well as the camera specifications also remain unchanged which means the phone has a vertical array with dual 12MP cameras.

The Z Flip 4 should have a slightly larger cover panel than the Flip 3
Other treats include the same two-tone design and a smooth, matte look. Like its predecessor, the Flip 4 apparently also has Armor Aluminum material and glass panels on the back and front.
Galaxy Z Flip 4 may offer a bigger battery
The source who leaked these images also revealed that the Galaxy Z Flip 4 has a longer battery life than the Flip 3, which means that the rumors about the increased battery capacity by 3,300 mAh at 3,700 mAh were fair. This seems to explain why the phone would be thicker than the outgoing model.
Users will also be able to recharge the battery quickly, as leaks indicate that the charging speed will be increased from 15W to 25W.