In the majority of cases where a phone is dropped, the device is just fine, but it is possible for a drop to damage a phone and affect its performance. These performance differences can range from bricking the phone to cracking the screen to other problems. Ultimately, a lot can go wrong, even if it’s usually fine.
It is perfectly fine to store a laptop vertically. If you want to be exceptionally proactive, store the laptop so that the vent doesn’t face the ceiling to prevent as much dust from collecting. Additionally, ensure that the laptop is stored securely so that it cannot fall over and take damage from a physical shock.
Hinge durability really depends on the model more than the brand. Most major computer manufacturers make a wide variety of computers intended for specific use cases. If you want tough hinges, then the best bet is to invest in a computer classified as a “rugged laptop,” which most major manufacturers produce.
In general, leaving the flashlight on, even for hours at a time, will not harm the flashlight itself or the phone. The flashlight can slowly contribute to battery drain, so if you have to do it for a long time, plug in the phone. In the long run, the flashlight will not cause any serious harm to the phone.