A customer recently asked us which size SwimCell he should buy for his Galaxy S7. So to show the different options we've used a Galaxy S5 Neo in a SwimCell waterproof case so that you can see the different fit.
The phone without it's silicon case measures 142 x 72.5 x 8.1 mm (5.59 x 2.85 x 0.32 in) so you can compare your phone to these measurements to give you an idea.
Image one shows the phone with it's silicon cover inside the large case. You can see there is lots of room in here so you could also add money and a key easily. You can also trap lots of air in here which will help the SwimCell to float if you weren't going to use it under the water.
When the Samsung is in the smaller case there is no extra space. The middle photo shows the phone with the silicon case and the 3rd has no silicon case. The 3rd is the best fit in our opinion but it's all a matter of preference as to whether you want the extra space or not.
We hope this helps, feel free to message us with any other questions that you have.
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