Depends which island.
We went to Sal and did an island tour. You could hire a car or buggy and do the same.
I’m not home so I can’t post examples, but I shot
Kite surfers
Baby sharks (go-pro)
Some interesting architecture (shanty town bright colours)
Fishermen preparing their catch
Some big skies
The salt lakes
Going back in February. And apparently there’s little to photograph or do on Boa Vista, so definitely go to Sal.