Don't want my iPhone 6s Plus anymore?

I bought an iPhone 6s Plus in december and I'm not able to adjust the size, I don't really like it anymore and I would love to switch to an iPhone 6s. However, I don't know if I can do that. How much would I have to pay? Any chance I could just switch it out for a smaller phone?

My iPhone is acting crazy all of a sudden?

Okay so I have an iPhone 5s through Sprint and I don't know why, but it's been acting insane lately. I recently updated to the iOS 9.2.1. I got the phone back in June 2014. I'll click an app multiple times and every time the app crashes. It doesn't matter which app it is (mail, twitter, safari, etc.). Then sometimes it'll randomly vibrate out of no where for like a minute (there's no water damage to the phone and I know it's not because I've received a notification). Sometimes the screen just goes black and stays black regardless of whatever button I press. Apple Music also doesn't work well. I create playlists and songs disappear from them or don't play. I'm honestly ready to throw my phone at the wall.

Advice on travelling photography?

I'm going to India in October and would like to take great pictures on my phone. I don't just want random blurry shots I take walking down the street trying to take a picture of everything. I have an iPhone 5s and my Instagram is private to me (I just like to have it to save my best photos) I'm not totally inexperienced but I want to just take incredible pictures of india for my Instagram, I'm only mentioning Instagram because I like the simplistic style it is all set out in and just so you have an idea of the style I'm going for. I just don't want a million rubbish pictures that don't represent what I see. I know loads of people take really amazing pictures using their iphones and other phones (my fiance also has a Samsung j5). I guess what I'm asking is are there any devices that attach to the phones or software or just anything that helps me capture the whole experience.

Why won't pictures open after getting hard drive transferred?

I took my laptop in a while back to have everything transferred to a new one. Now, some pictures from a family vacation won't open! It says "File format not supported," but all my other pictures will open and they were all taken on the same camera (iPhone). It's about the only vacation my family has ever taken so I'm really sad about it. Why would this be happening?

(PS the computer guy was extremely sketchy!)

How to pair Pebble Smartwatch with Spotify?

I got a Pebble (original) from my mom as she upgraded, and I had Itunes but chose to get spotify after my pebble was set up because I couldn't get it to pair with Itunes. I just downloaded songs and made playlists but I can't seem to pair it? I go to my music and it just says "no music found" is this because I got spotify AFTER setting up my pebble, or do I have to click something?