The Planet Waves NS Ukulele Capo is built for the uke.  That is a fairly rare statement these days.  Few companies are truly manufacturing capos that fit and work well on a ukulele and this is one of the best we have tried.

Not only is the squeeze small enough to be "just right", the small physical foot print of the capo minimizes the problem of the fretting hand running into it while playing open position chords.  

Thumbs up to Planet Waves for making a great capo that works exceptionally well on any uke!