I’m always filling up my phone with photos, and would love to have some simple way to store them online without taking up any space on my phone—that way, I could get to them if I need to, but they wouldn’t take up all the space on my phone.
The trick is to discern between the photos you want to keep on your phone and those you don't. If you need the photos on your phone no matter what, there’s not much you can do besides keep a conscious eye on the photos you have taken, and delete the ones you don’t need. On the other hand, there are photos you take that you just want to share or have on the Web somewhere, when you need them. And for that purpose, there is an easy app named Shutter from StreamNation (available for both Android and iOS).
Shutter provides free, unlimited storage for your photos (to get unlimited storage, you have to invite 5 friends—otherwise, you start with 5GB of storage, which should be plenty for most folks). Any photo you take with the Shutter app is immediately uploaded to your content on the StreamNation site. You control who can see your photos, and they take up no space on your device. Shutter seems like a really useful service, and you can learn more about it at http://www.streamnation.com/shutter.