Monday, May 11, 2009

Review: Navionics iPhone Charts V1.6 (again)

I got all excited over the weekend when iTunes downloaded an update to my Navionics chart application but on examination not sure what has changed - indeed it is labelled V1.6 just as the old one ones (probably part of ongoing laptop malaise which you don't want to know about).

However no harm in showing it again as have only just worked out how to get screenshots without using a camera. Ok, call me slow, but holding down the Menu and Off buttons at once doesn't seem to be the most intuitive of interfaces.

The first two pictures show the feature which tints locations for which there isn't sufficient depth blue. In this case they are around Cowes, with the picture above depth set to 2m and below to 5m.

But, and its big but, it uses depth of water given by chart datum, not taking into account tides.

Given the extreme tidal ranges we get - for example 6m on the Thames in central London - that is rather a significant flaw. And in theory Navionics software should know about tides.

However the tidal flow rate algorithm it uses appears to be bug ridden, so I for one wouldn't trust it. The figure below shows the prediction for a point off Portland Bill, near Weymouth Harbour (ignore that Plymouth text). Note the rather strange discontinuities.



I'm still hoping it will be updated at some point to full iNavX style functionality, but looks like will have to continue being patient.

Update! Version 2 software first impressions and screenshots.

Older posts on Navionics were as follows:
- Review: Navionics iPhone Charts V1.6
- Review: Navionics iPhone Charts Update
- Review: Navionics Charts