FLIP FLOPS: THE GOOD, THE BAD, AND THE UGLY —
First the good: an open shoe is good for air flow between toes and reduces the possibility of corns or blisters because there is no shoe pressure on bony prominences (bunions,hammertoes) on your foot.
Now the bad: the rubber strap between the big and second toes actually increases friction and moisture creating irritation, fungal infection and blistering. Also, the lack of support creates heel pain, arch fatigue and low back pain. Remember that your entire body weight is being supported by a thin strap between your toes. Keep these shoes at the poolside where they belong!
In sum: Flip-Flops do more bad than good
Alternatives: my favorite summer shoes are sandals with adjustable straps across the foot and a must have is a back strap. The adjustable straps will allow better fit across YOUR specific foot structures i.e. bunions, hammer toes, foot edema. The back strap will give you the best support when you are doing a lot of walking. Avoid plastic shoes. Look for leather uppers to reduce sweating and resultant fungal or wart infections.
Best: if your sandal has a molded arch bed with all these above-mentioned features, walking will be a breeze!