OK, so I put WhoGo through the paces and I must say, I am absolutely delighted. I'd like to emphasize that I have been using it exclusively in offline mode, with no SIM card in the phone, and it performed as expected in all situations. The routing is spot on, auto-rerouting works well and kicks in at just the right time when I take a diversion, the animations (tilt, rotation) are smooth and reflect the directions just right. Following the hints I received yesterday, the voice instructions work great too. Even the battery drain was better than expected: from 100% down to 71% after a one hour's drive yesterday and from 92% to 72% after about 45 minutes this morning.,

All in all, an excellent piece of work, on a par with some commercial alternatives.

Of course, it would not be me if I did not find some, let's just call them "potentials for improvement". Quite a lot of them related to the voice instructions. Some really trivial, others not so. Some essential, others maybe "would be nice to have", but not that crucial. Quite a lot of them are advanced features I cannot really expect from a product someone develops on his own, in his spare time.

So, here we go:

• As already mentioned, UK postcodes would be a very welcome addition. Having said that, I have used a commercial product that did not have a full postcode lookup and I had to use other methods, such as GPS coordinates (if available).
• It would be nice to have an option to save a location as a POI. For example, when you are on holiday, saving the hotel as the base would be quite useful.
• I am not sure you could do anything about this, but I find the roads rendered too narrow. I can only expand them when zooming in, at the expense of, well, having to zoom in, i.e. losing the big picture. And even then they are waaaaay too narrow. I would like them at least twice as wide, if not four or even five times. They will not be to scale but that does not matter.
• In fact, everything is far too small. I had the phone stuck with a sucker on the windscreen and could just about see the map and icon with the next manoeuvre and the distance, but not much else. The current speed, for example, is microscopic, totally unreadable at a distance between the driver's seat and the windscreen.
• Talking about the current speed, the speed limit info would be a welcome addition.
• This may be too much to ask, but speed camera locations would be nice too
• Back on the topic of things on the screen, I have noit figured out what the number under the current speed is supposed to represent. At first I thought it was the elevation, but that seems unlikely, given it shows figures like 3.3 yd.
• The voice instructions need some getting used to. I was at first confused with "enter the blurghburbhump and mumph the hunghxit", which, as I later figured out, was supposed to be, "enter the roundabout and take the third exit". After 10-15 minutes, I got used to it, but still confused with "rarautaut". It took about four times until I grokked that it was, "re-route found".
  Some of that confusion might be caused by the differences in accents. For example, "route" sounds like "root" in British English and "raut" in American. The way the thing pronounces "roundabout" is quite funny too.
• The voice instructions confuse yards and miles. As in, "in 700 miles, turn left", when the screen shows 0.4 miles, i.e. 700 yards.
• Some instructions sound a bit odd. For example, "continue for sixteen point miles". The word "point" is redundant. Another one, "four tenths of a mile". It may be cultural, but "zero point four miles" would sound more natural to me.
• In countries where you drive on the left, the roundabout icon is drawn the wrong way (see picture).
  
  
• It would be nice to have the number of the exit somehow incorporated in the icon. For example, in the middle. Roundabouts are very common in the UK so this would be a nice addition.
• Some instructions a way too verbose. "Take exit 4 on the left toward A404 etc", as in the picture, is way too much information. It covers too much of the screen and takes too long via voice. A simple "take the exit" would be perfectly OK.
  
  
• Sometimes, the instructions are a bit misleading, for example when an approach to the junction is a gentle curve in the direction opposite to actual target of the manoeuvre (see picture). Or, similarly, when the manoeuvre ends up being quite a sharp turn but the instructions suggest a gentle curve, because the approach begins gently. I have had a commercial satnav that did the same and I understand that it is not an easy nut to crack, but for example TomTom has managed.
  
  
• I said earlier that the animations are smooth and so they are, but the little symbol that shows your position keeps jumping forward and back. It looks like it is moving along the map and when too far, then the whole map including the symbol is jerked back. It is not too distracting but noticeable.
• I would prefer the ETA more visible, current speed much larger and included in the same area, and the blurb like "enter the roundabout and take the 4th exit" removed completely, but that might be only me. Perhaps making it configurable might be the way to go.
• In the landscape orientation, please consider moving the black info area from the top to the side.
• Please consider a wider range of map scale in Preferences. 0.5 to 2.0 seems more logical than 0.5 to 1.5.
• Some commercial satnavs display a progress bar, showing how far into the journey you are. WhoGo have that on the Navigation screen, which is nice, but including it in the main screen would be even nicer.

Phew, that was a lot! As I said, most of it is not really important, merely a "would be nice to have". I am currently completely out of cash and it is still only the start of the month with at least two payments still pending, so I am not in the position to send you a big donation, but rest assured I will as soon as I can. Please take whatever I am sending now as a token, just to save you in my PayPal list