WhatsApp has announced that it intends to focus on only 99.5 percent of the addressable mobile market, and will be dropping support for BlackBerry OS as well as BlackBerry 10, Nokia S40, and Nokia Symbian S60.
Along with the changes, the company said in a blog post it will also drop support for Android version 2.1 and 2.2, and Windows Phone 7.1.
"While these mobile devices have been an important part of our story, they don't offer the kind of capabilities we need to expand our app's features in the future," WhatsApp said.
The company explained that it intended to boost security features in the messaging service, and when it started out, around 70 percent of smartphones were either BlackBerry or Nokia, with Android, iOS, and Windows Phone now representing 99.5 percent of the market.
In the seven-day period ending February 1, Google reported that 0.1 percent of Android users were running Froyo 2.2.
Last month, WhatsApp dropped its $1 annual subscription fee, and said its subscription model had not worked well due to many of its users are without a debit or credit card.
The company said it would not introduce ads to make up for the revenue shortfall.
WhatsApp has recently been engaged in running battles with telecom regulators across the world. South Africa's two largest telcos, MTN and Vodacom, want to see over the top services regulated, while Brazil telcos are particularly miffed with WhatsApp offering voice call functionality and have sought to have WhatsApp declared illegal.
WhatsApp hit 1 billion monthly users earlier this month.