This is completely free; there are not even ads! In-App Billing is requested for future use; it is not yet used.
The app is an electronic version of an altimeter and vertical speed indicator (VSI) designed for pilots to use easily. It does not replace the need for an approved altimeter in your aircraft, but that does not mean it doesn't work. I envisage its main uses are as an emergency altimeter if the one on the aircraft fails, and as a tool to allow trainee pilots to learn the basics of altimetry.
It displays feet above the datum which can be expressed in either hectopascals (equivalent to millibars) or inches of mercury. There are buttons to decrease and increase the pressure datum by 10 units and 1 unit, and there is a special button to use to select pressure altitude which instantly sets 1013.25hPa. In this mode, it shows your flight level as well as the pressure altitude.
I have also added the capability to display a rolling 30s history of indicated altitude and vertical speed. How accurate is your straight and level flying? What about your level turns, rate 1, medium rate or steep? You can't focus on the altimeter or VSI while you are turning! With this, you can look at how well you did after the fact.
Perhaps you use an autopilot and you want to know how well it holds your level? This is probably the exact tool you need!
I have not yet tested it while flying because flying costs money and I don't have enough of it to do it very often, but one reviewer claims to have taken it flying and tested it successfully. What I have done is to set the local airport QNH over the last few days, and when I am at home, it always shows roughly the same altitude (within 30 feet or so). Also I have tested it on the beach with the nearest QNH set that I had available at the time, and the reading was very close to zero.
If you intend to make use of it while flying, please read the more extensive notes here beforehand:
You can also leave comments on that page. You can access that page through the "About" entry of the menu.
I have started a Google+ community for discussion of Phabvionics apps (at the time of writing, this is the only one):
A screen rotation causes loss of historic filter data at present. All that means is that you have to wait a few seconds (depending on the filter strength) to regain accurate indications and for the rolling history graph to catch up.
This version will not tell you if samples of pressure stop coming in. I'll add that feature back in soon.
I expect to fix the above problems in future versions.
Tags: pilot altimeter.
A rolling 30s history indication of vertical speed is now available. I also changed the defaults so that both this and the altitude history graph are enabled by default. If you need to disable them, that can be done in the configuration.
A rolling 30s history indication of altitude is now available. It is disabled by default, but easily enabled in the configuration.
Display in metres now available. Display in feet is selected by default.