1) Comfort. You’ll get nowhere without it. If you’re going to be jogging with a band around your arm it can’t chafe, can’t be constantly slipping, has to be adjustable to your arm size, and has to keep the Phone at a level above the elbow, but not too high into the armpit for easy movement. Look for designs that aren’t too bulky or heavy, don’t add extra length to the phone (or else you’re bound to have it all up in your elbow bend), and aren’t made of hard plastic or faux leather that’s going to chafe.
2) Water and Sweat Proofing. It’s essential. If the rain starts coming down while on a jog, you need to protect your Phone. Armbands with both a screen protector and a water proof back casing are a must. Look for designs with sweat proofing, because more than rain, it’s the sweat seeping from your arm that you’ll need to contend with when working out. Look for designs with moisture wicking material (they suck the water away so it can drip off, or bands made of neoprene, a very reliable, lightweight and waterproof material.
3) A Pouch For Key, Cash, or Cards. This is a double duty you’re bound to require. Who goes jogging without a house key? There are plenty of designs with a pocket specially designed for holding keys, a bit of cash, and maybe a debit card. Go for it if you’re like everyone else who sometimes wants to stop at the store on the way home for an energy drink, or to replace the milk you’re about to chug from the fridge.
4) Color Choices. Not everyone wants a black strap. While this isn’t essential, choice is power, and we’re talking about the best Phone armband here so if you want the best, get one where you can choose your look.
5) Adjustable Strap. Not because your arm is going to change size, but then if you’re working out, you’re hoping it will, aren’t you? Also though because summer running means sleeveless, while winter could mean a big jacket and you need to be able to strap the armband on around your coat sometimes. Velcro is great. There are also some sweet designs with a buckle strap like a watch or belt. Personally I prefer a Velcro with a long strip for precise sizing, but lots of people like a buckle with a good row of holes for when you’ve gone from scrawny to hulk and you want to be able to count the holes you’ve advanced along.