Windows Phone 7–Day 2 of UK tech.days

Today’s track was all about Windows Phone 7.

Brendan Watson talked about the Windows Phone Marketplace.

There are currently 17000 apps registered in the market place. The average selling price of an app is $2.93.

The Nokia deal will bring more carrier partnerships with countries where it’s difficult to get into (China for instance).

You can currently create apps in 30 countries but sell them in only 16. This number is expected to go up to 35 by the time Mango comes out.

Something clever about the market place: devs have the possibility to initiate beta testing programs.

Most of the other talks centred around UI design and performance. We heard a good number of tips and tricks from coders who faced specific performance issues when building apps and showed how to solve them.

Gergely Orosz described how his team spent a month discussing how Cocktail Flow would look like, building photoshop prototypes.

• small team, rapid prototyping and iteration.
• full visual plans with Photoshop and Flash. Several iterations.
• found inspiration in design guidelines for Windows Phone (MSDN)…
• …and YouTube videos of app demos

Some of his graphic design tips:

• You don’t have to stick with black (even if this is the default for most apps)
• Use images in menu items. Square images with grey frame look good.
• Use non dominant background images
• Keep dominant images for headers
• Spice up the buttons with gradients or different typo

Quotes from Gergely:

“Allow your designer gene to come out”

“Content is king but don’t ignore the chrome”

Oren Nachman gave lots of tips to optimise performance:

• Don’t use the ProgressBar control that comes out the box. It’s jerky. Instead use the PerformanceProgressBar from the Silverlight Toolkit.
• Enable RedrawRegions flag in debug mode to make it obvious when Silverlight is redrawing regions for no reason.
• Use the CacheMode property (on the WrapPanel for instance) to put images on the GPU and avoid redrawing them.
• Alternatives to the current ListBox: LongListSelector, LowProfileImageLoader

Also Oren mentioned that in the coming Mango release,

• the ListBox was completely revisited and will be faster.
• Networking: HttpWebRequest will take place on a background thread.