The Lava Discover line of cell phones are small, touchscreen phones primarily sold in India and southern Asian. For anyone looking to download and install WhatsApp onto their mobile device, there are really two methods, each based on the operating system used on the device. The Lava Discover mobile phones use either a Java based OS or Android. Both can handle WhatsApp but each is slightly different with the installation and specs.
Lava Discover 135
Released in 2013, the mobile phone has a 3.5 inch touchscreen offering 240 by 320 pixels. The phone offers a microSD card slot to increase phone storage by up to 4 gigabytes. The phone provides a 1.3 MP camera but no flash. The OS is based on the 
service provider, although the phone does support Wi-Fi and 3G (but not 4G). It also has 2 SIM card slots for easier international usage.
Lava Discover 136s
The 136s features a 3.5 inch touchscreen offering 320 by 480 resolution. It has a 1.3 MP camera and it does offer an LED flash, digital zoom and video recording capability. The microSD card slot can support up to 8 GB worth of data and it does have some Internet browsing features. The OS varies again based on the carrier, although most of the service providers have stuck to a more bare bones Java OS over Android.
Lava Discover 140
The 140 lineup of the phone makes a few general improvements but not too many over the previous models. It features a 3.5 inch touchscreen with 320 by 480 resolution. It supports a microSD card of up to 8 GB and has a 1.3 MP camera with video recording. However, this phone does not have LED flash. It also is primarily Java OS based.
Lava Discover 500
The Lava Discover 500 is a big upgrade from the 135. It offers a five inch touchscreen at 480 by 854 resolution. It has the same 4 GB storage upgrade potential and also supports dual SIM cards. It has a 5 MP rear camera and a secondary .3 front facing camera. This mobile phone runs Android OS.
Java OS
The operating system, especially for the earlier 135, is based primarily on the service provider. Some service providers choose to go with Java while others utilize the Google based Android OS. For the mobile phones running Java, it is necessary to open the Java application icon. From here, a user needs to type in “WhatsApp”, then download the app to the mobile phone.
If the Java store is not listed on the phone a user needs to download the application by connecting the device to their computer (through a Micro USB port), locate the Java Store page and download the application to their computer. From there they can drag and drop the application into the mobile phone like they would a file to a connected flash drive. Once WhatsApp has finished downloading and is installed, the user needs to open the app, type in the device’s mobile phone number and complete the activation process.
Google Android OS
The installation here is more straight forward. A Lava Discovery user on Android needs to open Google Play, type in “WhatsApp“, wait for it to download, then open the application following the installation. From here, they can type in the mobile phone’s number and finish the activation process.