Driving can be a dangerous activity when you only have the road to worry about, when you don't know where you're going and you need to consult SATNAV units or phones this becomes more dangerous.
You should never operate your phone while driving, so I hear you say use a phone clamp. The issue here is that it can be hard to find somewhere to locate the phone where it is visible but not blocking your line of sight.
A HUD (Heads Up Display), yes just like a fighter jet is the way.
These units are available to purchase but if you preferred to buy things you wouldn't be on instructables.
Step 1: The Plan
I had an unused lid from an electrical enclosure but you can use any sheet of clear or tinted (not coloured) perspex or poly-carbonate.
I placed my phone onto the sheet and traced around it, I used one of the side as a natural stop for the base of the handset.
I drew out retainers, uprights and finally a large screen area.
Step 2: Cut Out
I used a drill to mark each if the internal corners, this would help prevent over-runs with the cutter and give easy start points, this is important given the complex shape.
I then cut it out with the grinder wheel on the dremel.
I followed this with the sanding drum.
I know this is not the tidiest work but I was never good at staying inside the lines.
Step 3: Forming
Using a heat gun and a straight edge, I folded up each of the required edges.
The top screen was folded to approximately 45 degrees.
Step 4: Test
The phone fit well with the exception of needing to warp the retainer that was touching the volume key.
The image shown is with the lights on.
I don't have an image of it in use as you can only read it from the driver seat and it's not safe to photograph while driving.
The HUD app is Head-Up Nav (free in the android play store)