Power consumption
  • I am using a 7" tablet on a motorbike as "moving map". Because MFN shows almost no roads when beeing in overview-zoom-level I am using Osmand for map viewing (plus AFTrack for nmea-logging). Battery level in this case decreases about 10 % per hour with the device connected to board power (that's bad enough but I dindn't find a way to feed the tablet with more power). Short time ago hvdwolf mentioned something about "more roads visible in map mode" and therefore I decided to give it a new try. Besides the fact that i didn't see more roads than before I noticed that the battery level decreased about 18 % per hour, only displaying the map and logging nmea, without navigating. This means that after about 5 and a half hour the tablet went down and I had to switch to paper mode.
    Has anyone of you compared power consumption of MFN vs. some other navigation software?

    p.s.: When using a normal phone navigating with MFN the device stays on 100 %, so here it is no problem.
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  • HW renderer has multiply higher consuption than SW renderer. HW renderer consumes battery even when screen is off or navigator is active on background.
  • keep in mind that hardware rendering consumes more than software rendering
  • I read that earlier and therefore have always been using software renderer on that tablet.
  • I notice also that while navigating the battery capacity decreases gradually, so that after a trip of about 5 hours the battery is empty in spite of the device (a Samsung Galaxy S3) being connected to the board power network. Formerly (months ago) this didn't happen.
  • What's the "board power network" you're being connected to?
  • On sunny summer days, my car charger stops charging if the phone is too hot (to prevent explosion...) and it seems like the phone is consuming more power than the charger supplies, but indeed it blocks the charger's current..
  • I had a Google Nexus 7 (2012 version) which would discharge while navigating even when connected to a power source.
    I have since change to a Samsung Galaxy Tab A which charges even whist navigating with either hardware of software rendering.
    I suspect that the power drain problem is due to the device's charging hardware rather than Navigator. 
    Every device appears to behave differently!
  • Some devices (like galaxy s2 9.7'') require a stronger current. This used to be 500 mA. Some now require 2 A or 2.4 A. You car USB should be able to deliver a 2 A / 2.4 A current on one USB port, if the device requires this.
  • Most car USB ports definitely do not deliver this 2-2.4A. I do drive a lot of rental cars and have already driven at least 50+ car models/versions. When I connect my phone on the usb port it most of the times is not charged but simply slower drained.
    I almost always use a 12V plug with USB connect (with a strong enough power supply) as the 12V connections in a car most of the time deliver a much higher amperage than the usb port(s). And that's already for a phone, I can image that the difference is even greater for a tablet.
  • On android you have app (google play) like Ampere Meter, gives you the info on Ampere draw / delivery on your device.
  • Not all 12v to USB connectors deliver a high current. With some the current is intentionally limited, as it is with USB ports. You should check the spec.
  • and use correct cable or you won"t get the 2A

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