Mozilla has a new ad-blocker called Focus by Firefox for iOS users

The launch has kicked up the old debate of ad blockers choking revenues

Focus by Firefox blocks ads in Apple’s Safari browser on iOS but not in Mozilla’s own Firefox browser. Mozilla says that this was not a choice it made -- it’s an Apple limitation. (Mozilla)

Mozilla has launched a free content blocker for Safari users on Apple's iOS 9 operating system.

"Focus by Firefox puts users in control of their privacy by allowing them to block categories of trackers such as those used for ads, analytics and social media. Focus by Firefox may also increase performance and reduce mobile data usage by blocking Web fonts," Firefox said in a blog post.

You can install Focus by going to the iOS Apple Store. Simply run the app and configure it to banish ads on Safari. Focus only works on Safari and not Firefox, Mozilla's own browser, on iOS, but the company says that it couldn't help it -- Apple doesn't make content blocking available to third-party browsers on iOS.

To block or not to block?

The launch of Focus has revived the debate about ad blockers affecting publishers' revenues.

In September, a popular ad-blocker called Peace was pulled down from the App Store by developer Marco Arment. Among the reasons that he cited for taking down the app, Arment said that it "harmed the online ecosystem."

According to a Washington Post report , the debate over ad-blocking has spiraled into a much larger conversation about the future of blogs, newspapers and other online media. Ad blockers give users more control over their internet experience, but at the risk of undermining the very sites they depend on for information and entertainment.

"We believe content blockers need to be transparent with publishers and other content providers," Denelle Dixon-Thayer, a Mozilla executive, was quoted as saying to The Post "rather than placing certain content in a permanent penalty box."

Firefox OS is dead

Mozilla also canned its smartphone experiment by discontinuing Firefox OS, although the company will still continue to experiment on how it might work on other connected devices and Internet of Things networks.

Firefox OS was first unveiled in 2013, with the aim of targeting the developing world and late adopters with low-cost handsets. Several Indian manufacturers like Intex and Spice had joined hands to bring out these smartphones. (Firefox)

Firefox OS was first unveiled in 2013, with the aim of targeting the developing world and late adopters with low-cost handsets. Several Indian manufacturers like Intex and Spice had joined hands to bring out these smartphones. (Firefox)

"We are proud of the benefits Firefox OS added to the Web platform and will continue to experiment with the user experience across connected devices. We will build everything we do as a genuine open source project, focused on user experience first and build tools to enable the ecosystem to grow," TechCrunch quoted Ari Jaaksi, Mozilla's SVP of Connected Devices, as saying.

Firefox OS was first unveiled in 2013, with the aim of targeting the developing world and late adopters with low-cost handsets. Several Indian manufacturers like Intex and Spice had joined hands to bring out these smartphones.