Hi, I am looking for a tripod that could be used with both iPhone 6s+ and possibly normal cameras. I am looking for one that is standard size (i.e. normal one rather than very small and short ones), not so expensive. Any good suggestion?
The tripod extends to a maximum of 51", a bit more than four feet tall. Since I'm over six feet tall, that's way too short for a "full size" tripod. Since there's nothing particularly iPhone-related (the iPhone adapter is a separate accessory that can mount on just about any tripod), I wouldn't choose this one myself. The model I usually carry in my pack these days is the Manfrotto MKC3 - it extends to 60", weighs about 6 oz. more, and can be had for less than half the price of the model you've identified (I have three "full size" tripods of varying weight and features). You'll find that $150 can buy you a lot more tripod than is being offered at Apple.com.
The mounting adapter looks OK, but I've never seen it in person. There's a lot more out there than is being sold by Apple.