Popular messaging platform Whatsapp will stop working on a number of older iPhones and Android smartphones from next year. While few may lose access altogether, others may not be able to a few features on the platform.

As per reports, old smartphone users who have not upgraded to iOS 9 or above or Android 4.0.3 or above will not be able to run Whatsapp on their devices. In order to keep using it, the makers of the app said the users should update their devices to the said versions, failing which will deter them from using the Facebook-owned platform.

Users who are still holding on to the iPhone 4 or lower model will lose access. Similarly, if someone is using a Samsung Galaxy S2, he/she will not be able to use the software.

On iPhone devices system upgrade is easy as going into 'Settings' followed by 'General' and then tap on 'Software Update'. This will help them know which version of the OS they are running and whether they can upgrade or not. On the other hand, Android users will find it in the 'About Phone' section in the 'Settings' of their smartphone.

Some popular phones that will lose access to Whatsapp are – HTC Sensation, Samsung Google Nexus S, Sony Ericsson Xperia Arc, LG Optimus 2X, Samsung Galaxy S I9000, HTC Desire S, and others.