Unfortunately, when you realize the mistake, it is too late as there is no way to unsend the texts. This new feature will enable you to delete all your sent (probably accidental and embarrassing) messages before your receiver has had a chance to read them. The platform is testing this feature in Android as well as iOS apps and they may offer this feature in coming weeks.
Earlier this year, some users reportedly noticing signs of this feature on WhatsApp's code. Even worse, have you ever sent a message in error to the last person you'd ever want to receive it? However, since this feature is in beta, those who are not enrolled in the beta program have to wait for some time now.
According to the reports from the fan site WABetaInfo, the messaging app is finally testing the feature and it will be called as Delete for Everyone feature. In essence, the feature essentially blocks the message when it's stuck on the server. The deleted message will be updated in the Notification Center saying that the "sender has deleted the message". Better yet, if you decide to recall your message, whatever you wrote is not displayed on the recipient's notification area.
At this moment, it is hard to say when exactly this feature will be rolled out to the masses. The feature will be available for both Android and iOS users.