I'm not exactly sure what your phone is capable of, but I think you might just need to tinker with it a little more. There are apps available that can disable your lock screen or suspend it for a set amount of time. Search "no lock screen" in the Google Play Store (or your store of preference). I have an HTC EVO 4G LTE which was released April 2012. One of my favorite apps I use is the amazing app Tasker which I have set to, among other things, automatically disable my lock screen when I am connected to either my home or work Wi-Fi. Tasker could preform a similar action when my phone is docked in my vehicle or when a particular app is open. (i.e. Google Maps or Navigation) I also have Secure Settings which would allow me to place a widget on my desktop that would disable my lock screen with just one tap. And even without the fancy apps I can simply extend my lock screen timeout up to 30 minutes in the Settings menu with just a few clicks.
The capabilities of today's (and even yesterday's) phones are astounding. Perhaps you underestimate what yours can already do. If you can't adjust your lock timeout settings there most certainly are apps available that can fulfill your needs.
I'm posting this with hope this feature will be given serious thought by cell phone manufacturers who participate in this forum. The automatic screen lockout timer is a blessing and curse. It gives us peace of mind about security in case our phone is lost or stolen but it's a pain (and even adds to the danger of cell phone use while driving) when you need to use you need to look at your cell phone often such as using a map and/or GPS features on the phone. What is needed is the ability to temporarily suspend the cell phone screen lockout timer for a set period of time that is selectable. Maybe a few selections such as 10, 30 and 60 minutes would be good. This has been bugging me for a while in cell phones and I thought maybe by now some cell phone manufacturers would have this implemented. Maybe some have and I'd like to know who they are if so. It's not implemented in my LG Optimus smart phone I purchased last fall at least. Thanks.