"Building Windows Phone Apps: A Developer’s Guide" free PDF from those in the field (Think "Been there, done that, wrote the book...")

Building Windows Phone Apps: A Developer’s Guide

"This book combines useful, technical information about the platform, written by those who’ve been there and done it, with some stories about the people and the apps they’d written. The book will act as a handy reference that gives you a “puddy up” into developing on the platform and, importantly, helps you to avoid making the same mistakes others have made.

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Here's a snap of the PDF:

And the TOC;

Table of contents
Table of contents .................................................................................................................................... 2
Foreword ................................................................................................................................................. 3
Contributors ............................................................................................................................................ 4
Introduction ............................................................................................................................................ 9
Interlude: Football Crazy ....................................................................................................................... 11
The Windows Phone Developer Tools .................................................................................................. 14
Interlude: Going underground .............................................................................................................. 23
The Application Lifecycle ...................................................................................................................... 25
Interlude: Snow+Rock ........................................................................................................................... 29
Accessing Phone Features (launchers, choosers and input features) .................................................. 31
Interlude: Interactive sci-fi movies ....................................................................................................... 57
Location Aware Applications and Mapping .......................................................................................... 59
Interlude: How much is that taxi journey? ........................................................................................... 83
Reactive Extensions for .NET ................................................................................................................ 85
Interlude: Dude, where’s my car? ......................................................................................................... 92
Marketplace – Designing for First Time Approval................................................................................. 94
Interlude: Jobsite.co.uk goes mobile .................................................................................................... 98
A tour of libraries and samples ........................................................................................................... 100

Some light and inexpensive reading for the weekend... :)

(via ScottLogic -  Building Windows Phone Apps – a free WP7 eBook)