Really.
The DPE knows fltplan can plot the course
Your CFI knows fltplan can plot the course
You know fltplan can plot too
The question isn't can fltplan do it, we all know it can, the question is; given a ruler, pencle and chart can YOU plot the course.
The check-ride is where your student shows the DPE all the SKILLS he has learned, not his favorite websites and apps. God forbid the applicant is put in a situation where his trusty iWhatever F's up, then what, he commits hara kiri with his PDA stylus lol
God help 3/4 of you if one day I become a DPE lol
Whoa back there, cowboy. The DPE asked for a flight plan, he got a flight plan. I asked if he cared whether it was done with or without on line or other tools; he said he was OK with whatever method I cared to use. The main purpose was to see if I could follow the bloody thing and navigate my way to where we were headed.
During the oral exam (could have sworn I made this point before, but maybe I was not sufficiently clear) we clearly established (at least to his satisfaction) my familiarity with and ability to read and use sectional charts. We also covered my ability to perform all the tasks required to plan a flight. Fuel planning, wind correction, distance measurement, TSD calculations, weather planning, alternate airports, all that good stuff. Even W&B and takeoff and landing performance. It was almost like... I dunno... an oral exam.
So I use the tools I have available to gather the data I need. If the on line tools are unavailable, then it's back to a sectional, plotter and pencil. Not a problem. I always have the route marked on the sectional anyway, as well as elapsed times to various checkpoints. I don't fly with an iPad or whatever... I don't trust them, and they're distracting. But on the ground, I'll use whatever lessens the workload.
In fact, at the time I did my checkride I wasn't even using the panel-mounted Garmin 396; I knew I needed to be able to fly and navigate without it. The DPE asked why I wasn't using it, and I told him that. After we did the hood work and unusual attitudes, I had no idea where we were and told him I'd use a couple of VORs to find our position. He said he'd already seen me use VORs for navigation and we had already discussed triangulation, he'd rather see me use the GPS to get us home - so I did.
So. While your point is valid, you can feel free to hop down from the high horse. I know perfectly well how to plan a flight without using web sites. The DPE knows I can do it. I am quite capable of using a pencil, pen or whatever other writing implement you might feel is required.