This was not the first time that this happened. Just down the way a little bit I was told that the guys were fishing in 18 feet of water where it showed less than 10 on the map. On one particular lake I went out an thought that I would be in 10-15 feet of water but in fact I was only in 7 feet. The positioning on the app works very well but so far I am not at all convinced as to the accuracy of the depths associated with the contours. I do a lot of ice fishing and thought that this would be ideal for locating holes and proper depths for what I am looking for. I purchased the Canada/USA version at Christmas as I am an avid fisherman and like to try different lakes. Not too impressed with this app for ice fishing so far. If buying electronic charts make sure they are UKHO licenced and are up to date. Older Raymarine chartplotters only use Navionics charts - so if you are forced to used them make sure you have up to date paper charts to refer to. I teach sailing in the Solent and I use Navionics to illustrate to students why they should NOT rely on electronic charts. The RYA have now entered a sponsorship deal with Navionics, which I think should be stopped immediately with a warning to member NOT to use it. Navionics has 2000 updates per day as they find, or have reported to them, 2000 errors per day. They had totally missed Eddystone lighthouse off the phone app charts until I pointed it out to them. Navionics also shows (or did last time I looked) a yellow bouy in the channel past the Needles into the Solent - it does not exist. I have photos of chart plotters showing 16+m of water, whilst looking at a row of small islands - thank goodness it was daylight at the time, at night we would have sailed straight into them. I have delivered yachts throughout the Med and UK, many boats have Navionics plotters etc, and I have used phone and tablet apps. They do not have a licence from HMSO/UKHO to use official charts, instead they cobble together sources, including user information, notice to mariners etc. Far more important is the extremely poor quality of chart data they provide. Most comments seem to be about the cost and poor customer service.