Unfortunately, for the average user, iOS 10 isn't yet available. It slated to do a public beta in July and then be released some time in the fall, with a host of promising features and then some less necessary features, like making emojis three times larger.
There are a lot of questions to sort still, like what will happen if you click an email address but have deleted the Mail app? Can it default to Gmail? Or you can make Google Maps your default map application? Right now, it's not doing that. But that doesn't mean that will necessarily be the case on the public release in the fall.
Some of the stock apps are here to stay, like the App Store, Safari, and Game Center. But here is the full list, according to Verge, of apps that will become removeable with the release of iOS 10.
- Find My Friends
- iCloud Drive
- iTunes Store
- Voice Memos
- Watch app