The document discusses building rich internet applications (RIAs) from the perspective of finger tip size on mobile devices. It notes that pixels per inch (PPI) is a better metric than dots per inch (DPI) for mobile screens. A finger tip is used as a baseline unit of measurement, estimated to be around 8x5 finger tips on a Nexus One screen. The document recommends using a baseline PPI of 254 for the Nexus One and scaling layouts relative to different PPIs. It provides suggestions for layout helpers, font sizes, images and constraints to account for varying PPIs across devices.

1. Building RIAs from the Perspective of the Finger Tip Renaun Erickson Platform Evangelist

3. The Difference Between DPI and PPI

4. How Large is a Finger Tip

5. Scaling Relative to PPI

6. Layout Helpers for Large Content

9. 1153x813

11. Mac DPI is set to 72

12. Desktop’s Typically don’t factor in Monitor’s physical dimension, scaling then happens for you.

13. DPI is highly used with Printers

16. What’s Your Devices Size in Finger Tip Finger Tip Size for Nexus One ~ 8 x 5 Finger Tips

18. Consider layout constraints with up to 1/2 scaling.

19. Scaling up causes pixilation.

21. 100px x 100px Button

24. PhysicalSizeUtil provides pan/move of component

25. (Future Idea) PhysicalSizeUtilprovides auto pan/move for spark Form

26. As the user fills out FormItems it will center on the next item for them

27. Opt in to layout helpers and style scaling.

29. 24 Font Size

30. Embed Fonts (Both for Scaling and OS issues)

31. Images at higher resolutions.

32. Layout applications with Constraints.

34. Q/A Flash Player 10.1 Desktop and Android – http://www.adobe.com/go/getflash/ AIR for Android - http://labs.adobe.com/technologies/air2/android/ Twitter: @renaun Blog: http://renaun.com Email: renaun@adobe.com