Instagram is perfect photo and experienced sharing site, you get the fun photos of your friends and family without all the drama of facebook posts and stupid comments. And the filters make it even more fun. Easy to use on the sony xperia z1
I also store store my images on my instagram acc if I ran out of space instagram also has option to link my other social networking sites like fb, twitter etc
The only drawback is that it does not has more filters option it would be great if more filters would be added and for that I use another app called retrica for android which has many filters options