On 19 July, Apple released beta 3, which adds a few new tweaks to the mobile operating platform. Whilst on 2 August Apple released beta 4 bringing new feautres and even replaces the pistol revolver emoji with a green water gun. In mid-August, Apple released beta 5 to the public and beta 6 to developers.
The developer preview beta version of iOS is also available, but you'll need a developer account to get it. If you're keen, read more here: How to get iOS 10 on your iPhone/iPad now. (If you change your mind afterwards, see How to remove iOS 10 and reinstall iOS 9.)