One of the many things Apple revealed at its worldwide developer conference last month was the upgrades that iOS 10 would bring to iMessage, such as the ability to use GIF-like animated stickers. Now, the company has shown what people can expect by releasing four of the sticker packs for the beta version of its upcoming OS.

The iOS 10 feature allows third-party developers to create their own animated emojis or GIF packs using the Messages application program interface (API). The four sticker packs currently available through iTunes Preview are Smileys, Hearts, Hands, and Classic Mac.

The Classic Mac pack contains a series of black and white icons originally created by graphic designer Susan Kare in the 80s. The others are, as the names suggest, a mixture of animated hearts, 3D smileys, and hand gestures such as the peace sign and thumbs up.

The stickers can be accessed in the iMessages app drawer once installed. They can be added to conversations, placed around chat bubbles, stuck onto images, and even plastered over the top of other stickers.

Another Messages feature set to appear in iOS 10 is the "invisible ink" option that hides a response until the recipient slides their finger over a message to reveal it. Additionally, emojis will be three times larger and are automatically recommended as you type in the same way as predictive text.

Expect to see a lot more sticker packs, along with other third-party add-ons for the Messages platform, when iOS 10 is released later this year.