Okay, first of all, I am a newbie to my Samsung Galaxy S3 phone, and am constantly finding myself closing screens and doing other unexpected things, so some of what I am about to share may simply be my ineptitude using a smartphone. In any case, here goes:
I just returned from a 10 day ride through NY, PA, WV, VA, MD, then back home through more PA and NY. My Galaxy S3 is my first smart phone, and I found the weather radar very useful on day 2 of our ride, when we were dodging thunderstorms most of the day. Unfortunately, using the smartphone as a portable GPS has one major flaw, which is screen brightness. I kept my phone in the clear window of my tankbag, and really could not see it unless I stopped and cupped a hand over it. Having used an inexpensive Garmin auto GPS on my bike in the past, I found that screen to be brighter and easier to read.
I also got a message that the server was unavailable, or some other line like that, about 50% of the time when I was trying to use the program. I ended up using the maps app built in to the phone, as it always worked okay. Unfortunately, it only keeps the display on when you have it in navigate, and I wanted to use the map view, but had to use the navigate view instead or the screen shut down.
While I hate Google maps online, as it always seems to freeze and/or lose a bunch of my route when I am making a new one, the ability to drag to diferent routes rather than the suggested one is an essential feature if one wishes to avoid riding interstates all day, and something I really missed with both the map app and your software.
I also wish I could enter the destination by typing rather than only by voice. I have to admit the voice entry worked pretty well the majority of the time, but it sometimes didn't understand.
I ended up using the phone's built in map app to make my next day's route each night, by entering my destination and then finding better looking secondary roads along the route, and writing a turn-by-turn route on large index cards for my tank bag. (I had done a similar process at home for the first day's ride, using the Delorme Gazetteer for NY, which is an awesome and easy way to build a great route.) Zooming out to see if I was staying somewhere in the vicinity of the blue route line kept me going in the correct general direction. I then used your app to check the live radar each day to see how things looked before setting off.
For my needs, I would like to see the ability to drag and change a route to build it, and then a button that puts the actual turn by turn directions on the phone screen in huge and highly contrasting letters (in landscape view), with the distance until the next turn underneath. No maps or pictures, etc., just the simple arrow indicating direction of upcoming turn, and the distance left underneath. Probably way to much to ask of a $12 app, but you did ask for suggestions.