10 Best sailing apps (android)
Android market https://play.google.com/store?hl=en

Many of the articles covering sailing apps are very US focused. As US charting, weather and tide information does not apply anywhere else in the world, we are keeping a close eye on apps that have broader applications. After all, cruisers and racers tend to sail all over the place whether on their own boat or OPBs (other people’s boats).

For Android (as of March 2012)
1.   Navionics Charts
2.   NOAA Buoy and Tide Data
3.   Passage Weather
4.   Tide Graph
5.   EarthNC (with Google Earth integration)
covers US, Bahamas, New Zealand and Brazil
6.   PredictWind
7.   PocketNav (integrates with ActiveCaptain)
8.   Marine Charts
9.   Google Sky Map
10.   Boater’s Pocket Reference

Here are some other neat apps:
Ship Finder
RYA Handy Racing Rules
Nautical chart symbols
SAS Survival Guide
Currents
Buoy Weather
Weather Eye
Marine Traffic
Memory-Map (NOAA Raster charts)
MxMariner
Marine Charts HD & Lite
NutiCharts Lite
AveTides
Tides Planner 10
Tide Graph
Tidal Chronoscope
History of sailing
Tide7 (UK, Ireland, Benelux)
Marine Traffic
Racing Rules of Sailing (US Sailing) [Costs €4.43 and has some pretty bad user ratings.]

Vice Commodore, OCC 

Sail-World just posted a story about Boat Beacon, an iPad app now available in android that sounds almost too good to be true. It downloads and transmits AIS data to your smart phone. Does anyone have experience with it?

From Sail-World...http://www.sail-world.com/index.cfm?nid=101413

"Boat Beacon offers a professional, easy and inexpensive way to experience the benefits of AIS navigation. Features of Boat Beacon include:
1. Real-time 'Map View ' of both the user’s and other boats via AIS.
2. Continuous Collision detection using Closest Point of Approach (CPA)
3. 'Compass ' mode to sight ships on the map including bearing to and distance from.
4. Enable friends and family to see the user’s location and course on Boat Beacon and Global AIS Systems.
5. Current Speed, Course and GPS location
6. Details about other ships including photos.
7. MMSI numbers to contact nearby boats via VHF.

By enabling Boat Beacon’s 'Transmit ' mode, the user’s boat will appear on other Boat Beacon-equipped devices. With its AIS Sharing feature, the user’s boat will also appear on live ship tracking websites such as AIS Hub, Marine Traffic and Ship Finder."

Vice Commodore, OCC