After Facebook purchased Whatsapp for a whopping $19 bn, there was mass-migration to other messenger apps built for the iPhone. As such, there's no indication that your data is going to be used or that the original Whatsapp experience is going to be altered in a bad way but the verdict is kind of clear. Many people are moving away from Whatsapp.
If you had been looking around for suitable alternatives prior to the Facebook-Whatsapp deal (or after it), we had it covered a long time back. One notable addition was Telegram which truly is one of the perfect alternatives to Whatsapp (for its minimalism, speed and security features). But Telegram is not all. There are others.
Cast your vote for Whatsapp alternatives for iPhone:
Apps like LINE and Kik have a decently good interface and features too although nothing comes quite as close to Telegram in terms of speed. The one big complaint I can raise against all these Whatsapp-alternatives is that the apps contain too many features that creates a lag in the overall experience. I used Hike for quite sometime before realizing how awfully slow it was on iOS 7. WeChat has similar issues with tons of features that, a sworn minimalist, would call bloat.
But there are viable alternatives, if not permanently, at least temporarily. There are some lesser-known alternatives in Surespot and BBM. Surespot, for instance, offers high-end security and is actually very-focused on keeping the messages as secure as possible even beyond Telegram's sworn adherence to secure messaging.
There are also old players like Viber and Samsung's ChatOn that you could try. And then there is Google's Hangouts and Microsoft's Skype – two services that I have had bad experiences with.
Telegram started seeing 5 million new sign-ups every day, after the Facebook-Whatsapp deal became news. This app definitely has catapulted after Facebook purchased Whatsapp. The founder/CEO has said that the focus is on building something to let users communicate so there would be no monetization in the form of ads, no focus on maximizing user-base or no sellouts.
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