Following is a list of a few GPS Car Navigation Apps that  
work with the Z1 and also my experience with them.
 
Sygic > Best one so far. 7 day demo available in the Google Play Store.
Osmand > Works but difficult to use
Navit > Works but even more difficult, cannot hear voice nav
Be on road > Still testing
Navfree > Will test later on
Tomtom > Incompatible with Z1 so no install, no updates  
Garmin  > Incompatible with Z1 so no install, no updates  
 
If any of you guys has success with
any GPS Car Navigation Apps for the Z1 please post here..
 
 
 
Sygic use:
 
Remember to slightly longpress each tap and wait a little after tapping!
Z1 is a little slow with Car Navigation Apps.
 
The very 1st time Sygic will start it will go immediately to map selection.
After downloading a map [for example America > California
Sygic will initialise. Then you will select a language [English US]
and a voice as follows:
 
Tap the current voice and swipe upwards to view
a TTS Voice, then tap TTS American English (Allison)
[ my favorite :^) ]
then tap back and tap continue.
 
Make sure you select TTS voices!
TTS is very important as Sygic with TTS can speak the names of streets
since your eyes SHOULD BE ON THE ROAD..
and also makes navigation so much easier.
 
 
 
Before doing any navigation go to:
 
Settings > Map > Autozoom
 
Disable Autozoom.. [untick]
it will constantly crash Sygic.
 
 
 
To Navigate tap:
 
Navigate to.. > Address or POI >  
Tap town / Tap Select City / Tap Select Street THEN enter number of street
Tap Done at right down corner.
 
Swipe down and tap Add to favorites [recommended] then tap Done
OR
Tap Drive to > Done to start Navigation.
 
After reaching your destination ALWAYS do the following:
Tap Route > Cancel route
 
If you don't cancel, next time you start Sygic it will crash when it will go to the map screen.
 
 
 
Use of Favorites:
 
Tap Navigate to.. > Favorites > [yourfavorite] > Drive to > Done
 
To Add a favorite POI [Point of Interest]:
 
Tap Navigate to.. > Nearby POI > [poi-that-u-like] > Add to favorites  
 
To add any location to the list of favorites that your car is currently parked:
 
Tap Navigate to.. > Favorites > [dismiss search] > Add > My current position
 
 
 
To download more maps:
 
Start Sygic then tap My Sygic > Manage Maps
and select map to download
[for example tap US-California > Proceed]
 
 
 
Hope the above helps!
 
ff

 
You are probably using an audio effect that somehow blocks the voice of Sygic..
 
Goto Settings > Audio effect > and untick the Audio effect option to disable it.
 
Maybe restart your Z1.
 
Let me know if it works.  
 
Quote from Dragon_fist on Dec 29^th, 2012, 3:23pm:

It works,coool ,  I switched off the audio effect Thank you soooooooo much!!! Best regards Dragon_fist
 
Quote from ffinder on Jan 9^th, 2013, 11:23pm:

Sygic > Best one so far. 7 day demo available in the Google Play Store.
Osmand > Works but difficult to use