I have two options 1. Buying 7" tablet and i make "fixed" installation to front of 4x4/navi display 2. Replacing existing player which have bluetooth so i can play it from Iphone. Need to remain handsfree function. 1. Is price wise around 300 euros inc new tablet 2. Price ?

The head unit provides the interface between the CANBUS and the MOST loop, so if you remove it, you will have to loose the navigation, bluetooth, voice control etc. and, should you have had it enabled, the clock on the dash. I believe it has been relocated elsewhere in the car previously to retain the functions - a search on Disco3 should produce results.

By far the easiest and cheapest way would simply be to plug in a bluetooth receiver to the aux input.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

Thats clear. Phone is already connected to hands free and Tom Tom navigator so im not sure is good option to stream from Phone anymore. Migth go with separate music player and maybe i use it as an navigator also. And maybe even something else also.

I am still considering buying this unit:
http://lsqbusiness.en.alibaba.com/product/..._NAVI.html
(though I have still my doubts in regards of quality and there is no Central Europe map, which is a major bummer for me). Regards etc.,

Wojtek

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WAS: 2006 RRS Supercharged
IS: 2010 RRS TDV8 HSE

I bought cheap and simple 7 " Android table. You can have Navi ( google maps), spotify, youtube etc.
Physical installation is still open most likely with active Brodit stand to front of original display.
One reason not to play music from Iphone is that for some reason music does not come out from IOS products as loud from Android. When installation is ready i can put some picts...