Last Sunday I decided my Technology Mission would be to not use Snapchat for a week. I uninstalled the app on Monday morning and I'll probably reinstall it this coming Monday or Tuesday. I think it would be good to go a full week without it. I can't say I've been missing it too much and may consider permanently deleting my account. I realize deleting my account might be a little extreme, so I should take a longer break from Snapchat before making that decision. I deleted Instagram completely once and ended up reinstalling it, so I don't want that to end up happening again with Snapchat.
Now in terms of the app saving stuff to your phone, it is "minimalistic" in that it doesn't save pictures/videos to your phone by default. You have to choose to save pictures/videos you capture. Also, viewed photos/videos from other people aren't saved to your phone, unless, again, you choose to by taking a screenshot. I don't know if I've been using my phone less, and I may be using my phone for the same amount of time, just using other apps for social media to make up for the difference of not having Snapchat.
I guess out of Facebook, Twitter, Instagram, and Snapchat, Snapchat seems the most disposable to me. I've used FB and Twitter a lot longer, and I like seeing pictures of my friends/family on Instagram. Updates and changes will come to Snapchat to establish and maintain it's place as a top social media app, and also since the company will probably be taken public some day, and those investors/stock holders will want to see the $'s rolling in. Some of those future changes and updates could make me want to use Snapchat more, but right now, I'm not overly attached to it.
Side note - There was also a small update to the Robinhood App. The app is now on version 1.4.2. The only thing listed for this update was fixes for bugs.