A WhatsApp message has been doing the rounds on Facebook recently, with a pretty bold statement. ¡°If you touch the black point your WhatsApp will hang,¡± it boldly declares, with said black spot lower in the message. And sure enough, if you touch it, your app hangs, even if only momentarily.
So, are we now living in the new age of cyber voodoo? Of course not. There are actually a few ways that you can mess with a simple messaging client, and one of them is by including symbols it doesn¡¯t recognise. In this case, it¡¯s not the obvious black spot here causing the problem, but actually the blank space right after it.
When you convert the message into HTML you can see just how mischievous this innocuous little message is. That repetition of ¡°? &rlm:¡± are actually something that¡¯s called a control character. In HTML, this denotes the alignment of a piece of text that might be different than that of the text around it.
For example, if you¡¯re writing a Word document in Urdu, the text runs from right to left. Now, if you want to put an English word in here, it¡¯ll be scrambled by that alignment. Instead, you use this control character to specify this word is instead aligned left to right ($lrm;).
In this case, the creator of this message can use multiple of them to momentarily overwhelm your WhatsApp (at least for Android users). You don¡¯t see it either because this is an invisible character. That¡¯s why, with a touch interface, tapping on the first part of text here does nothing, whereas tapping on anything after is what causes the app to hang.
So no, it¡¯s not WhatsApp magic, just a troll with technical knowledge and too much time on their hands.