One thing I forgot to add is that Ranger is my hearing ear service dog. I trained him myself.
One night, he woke me up at 3 in the morining, and wouldn't let me go back to sleep. I couldn't figure out what the heck he wanted. Finally, the third time he poked me, I woke up enough to realize maybe he was trying to alert me to something I couldn't hear. I said, "What is it, Ranger?" He led me out into the dining room, and looked up at the smoke alarm. It was doing the low battery beep!
I took the battery out (there was another alarm in the room, the one I used to reinforce his training) and he finally let me go back to sleep!
The one part of his training I needed help with was alerting to the door, as he'd been an outdoor dog, and didn't know what a knock on the door meant. It took myself and a professional trainer 10 minutes to teach him that. It took about 2 minutes to teach him to alert to the kitchen timer.
The first thing I trained him for was the alarm clock. As my alarm also had a bed shaker, this was just a fun thing. I think I did 2 or 3 sessions with him, then didn't bother with any more.
One morning, he put his paws up on the bed, and nudged me awake. As the alarm hadn't gone off yet, I just ignored him. When he did it a second time, I decided I'd better pay attention, as he might be telling me he needed to go out.
When I rolled over, I found the bed shaker had quit on me, and he was trying to tell me the alarm had been going off for the last 15 minutes. Because I ignored him, I was nearly late for work!
Since I'd done so few training sessions with the alarm, I hadn't thought that was enough for him to alert to it reliably. Some trainers will tell you it takes 100 repetitions for the dog to be trained reliably to a task.
They don't know German Shepherds very well....