The Signal Private Messenger app now tops the list of ‘Best Free Apps’ in Apple’s App Store. WhatsApp is in third place. This shows the popularity of the signal. A signal spokesman said the number of new users coming to the platform had increased. As a result, there are delays in verifying the phone numbers of new accounts, the signal said. Many new users are coming in every second to try out the app run by the non-profit Signal Foundation.The app is available on Android and iOS. Unlike WhatsApp, Signal is also available on the iPad. Additionally, users can download and install the Signal application on Windows, Linux, and Mac.