Nokiaand operating system that it hopes can help it compete with Android phones at the low end of the mobile market.
The 2G touchscreen handset features a single homepage to access both apps and calling function, as well as the option to swipe to Nokia's 'Fastlane' page which lists recently used apps, contacts and social network updates.
Like other Series 40 handsets, the 501 features Nokia's Xpress browser, which compresses web pages by 90 percent to cut data usage: handy in markets where all-you-can-eat data, and even 3G, can be a rarity. And, like previous Ashas, applications written for the Nokia Asha 501 will not have to be re-written for future models, Nokia said.
Nokia is also promising a beta of an in-app payment tool for the Asha platform in the coming weeks, allowing developers to sell content from within their apps.
The 501 – which will retail for $99 before taxes and subsidies — is aimed at taking on Android in emerging markets, and Nokia is predicting it will sell 100 million devices running on the new Asha platform "over the coming years".
While Nokia cheerfully describes the Asha as a smartphone,.
"It does re-open that question of what is a smartphone and what isn't and it's a difficult question to answer," said Tony Cripps, principal analyst at Ovum.
There have been all kinds of definitions of the smartphone over the years, almost none of which work in practice, said Cripps: "It's quite difficult to define a smartphone based on any distinctive criteria, ones that really do separate smartphones from other phones — something like the Asha throws this into relief once again," he said.
But Cripps added: "We've adopted the stance that [for] the Asha platform we won't consider devices running it to be smartphones on the basis that it's really taking an operating system that was designed around feature phones."
Still, for most users the distinction between smart and feature phones will be irrelevant so long as they can get hold of the apps they want — and Nokia said applications are already available or in development for the Asha platform including Facebook, Foursquare, and LinkedIn, while adding somewhat vaguely: "WhatsApp and other key partners continue to explore new Asha."
Reiterating smartphone like qualities of the 501 and the Asha platform is aimed at helping Nokia fight off Android at the low end of the mobile market – there are plenty of cheap and cheerful $100 Android devices but Nokia will be hoping that by talking up Ashas' apps and using similar design for the 510 as its high-end Lumia phones, the Asha range will be able to win over an aspirational, younger audience who might normally buy Android.
Cripps said: "Nokia is making the best of a bad deal. They've got an operating system in Windows Phone that started off at the high-end and is working its way down bit by bit, and at the other end, they've got Series 40 which was designed for much lower-cost less feature-rich devices and that's creeping up.
"There's a sense I still have that there's a gap — that ultimately Windows Phone can't reach down into the $100 category and equally it's hard to conceive of how these Asha devices can much exceed what they're currently doing, so there is, I think, still a gap in the Nokia portfolio."
The Asha is one half of Nokia's strategy – the other is the high-end Lumia phones which run Microsoft's Windows Phone operating system. The company has spent the last two years moving away from Symbian as its core operating system but sales of Lumias have not grown as fast as it has hoped, leading to frustration from shareholders.
But for Cripps, leaping off the burning platform of Symbian into the arms of Microsoft was still the best choice for the Finnish handset maker. "For Nokia they wanted to maintain a level of distinctiveness and that wasn't going to be possible if they adopted Android. Nokia are the custodians of Windows Phone — it almost, de facto, becomes their platform as far as the handset market is concerned. If they want to be in charge of their own destiny then it's probably better to go with Windows Phone than Android."