It's not a shocking move when Rakuten is one of the largest online retailers on the planet and wants to fend off both chat rivals like Facebook and shopping behemoths like Amazon. If you can find what you want right from your phone's keyboard, you're less likely to switch chat apps or link to a competing store.

And despite the in-your-face nature of the keyboard's shopping feature, it has a fair number of takers. The Viber team says that 30 percent of its American users have tried Instant Shopping since launch. The big challenge is keeping your attention: it's easy to try a shopping feature when it's fresh, but it's another to treat it as your go-to option. That's where the acquisition might help. Now that Rakuten Viber owns its shopping keyboard partner, it can improve and grow features on its terms. If it can improve the keyboard and add more shopping partners, you may have more reasons to stick around.