25/07/2012 16:15 | By Stuart Dredge, contributor, MSN Tech & Gadgets

Whale Trail Frenzy: app of the day

Soar through the skies with bubbles, clouds and Super Furry Animals.

Whale Trail Frenzy (© Image © Whale Trail Frenzy)

What is it?
A new 'freemium' take on existing mobile game Whale Trail, from UK studio ustwo. Inspired by games like Tiny Wings, it sees you flying a whale through the clouds, collecting bubbles as you go.

Coolest feature
Like the paid versions of the game, Super Furry Animal Gruff Rhys contributes a marvellously-woozy theme tune. Meanwhile, the fact that Whale Trail is now free to play should make it available to a wider audience.

Android - Free

When it came out for iOS in 2011, Whale Trail was a psychedelic treat: an "endless flyer" game that involved piloting a cute cartoon whale called Willow through the skies, collecting bubbles and avoiding clouds.

It sold fairly well, and was joined by an Android version in January 2012. However, ustwo has spent the intervening months reworking Whale Trail as a freemium game: free to play, with in-app purchases used to buy 'krill' virtual currency to spend on upgrading Willow's abilities.

On iOS, the freemium version replaced the existing paid game, provoking an angry reaction from some players who felt they were being forced to pay all over again to get the most out of the game.

On Android, ustwo has taken a different approach: Whale Trail Frenzy is the new, separate freemium game, joining the renamed Whale Trail Classic on the Google Play Store, rather than replacing it.

That's the back-story, but how is the game? Marvellous.

You control Willow by holding your finger on the screen to make her rise, and taking it off to let her drop - anyone who's played Tiny Wings will feel at home straight away.

You fuel Willow's flight by collecting colourful bubbles, while avoiding crashing into clouds. Mess it up, and you plummet off the bottom of the screen: game over. Stars appear too: collect enough, and you go into 'Frenzy' mode, which automatically sucks in bubbles while letting you smash through clouds unharmed.

The visuals are bright and distinctly psychedelic, and the theme tune from Super Furry Animals frontman Gruff Rhys remains a treat, sticking in your head long after you put your device down.

This Frenzy edition has two game modes: Classic and Challenge. Classic is the basic game: fly until you die, accumulating as high a score as possible in the process. Challenge is more akin to Angry Birds' structure: 64 levels and a three-star rating system for your skills on each.

Whale Tail Frenzy (© Image © Whale Tail Frenzy)

The freemium part comes with the krill virtual currency. You can earn it by playing, or buy it using the Android in-app purchases system. Krill can then be spent in the 'Krill Store' on upgrading Willow's skills - frenzy length, cloud resistance, max multiplier and so on - as well as limited-use power-ups like a respawn, 8x score multiplier and 'Insta Frenzy'.

It feels like ustwo has pitched the balance about right here: you can happily play Whale Trail Frenzy for free and feel like you're progressing without being put under pressure to pay. In fact, playing the game is a woozy, relaxed experience - it doesn't feel like a currency-focused grind.

See also - Top 50 iPad apps

Whale Trail was a great game in its paid version, and it's negotiated the switch to freemium well. Here's hoping it now gets to work its charms on many more people.

Five stars