Hearthstone: Heroes of Warcraft will be available for Android tablets before the end of the year, Blizzard has announced.

"We're taking things one step at a time and we've got our sights set on a release for Android tablets, our next new platform, before the end of the year," wrote Blizzard. "We've just got a few more mana crystals to polish and some Angry Chickens to chase down."

In the same update, Blizzard announced that the long-awaited iPhone and Android phone editions were still some way from completion.

"We're also close to having Hearthstone out to our iPhone and Android phone users, but it's become clear that we need a little more time to get that version right," the developer said. "While we have a build up and running internally, it needs a bit more work, and we don't feel like we'll be ready to share it with you until early next year."

"It's very important to us that the phone experience for Hearthstone is just as accessible as the tablet and PC versions. One of the biggest challenges with that is revamping the user interface so it feels intuitive and offers the same quality Hearthstone experience, but this time from the palm of your hand."

"Releasing Hearthstone on iPhone and Android phones is something we're incredibly excited about, but ultimately we'd rather take the extra time to make Hearthstone's user interface on the phone customised to feel great for the platform, rather than a port that doesn't taken into account the limitations of a smaller screen."

More than 20 million people have played Hearthstone: Heroes of Warcraft.

Hearthstone came out of beta on PC and Mac in March. The free-to-play collectible card game is also currently available on iPad.