When I was a PPL student, calculating a weight and balance (W&B) schedule for a flight took about 20 minutes using a form, the POH and a fair amount of mathematics. It wasn’t difficult but it was fiddly and time-consuming.
Every year there are accidents where pilots wilfully or accidentally overload or unbalance their aircraft with tragic results so W&B definitely matters.
I’m slowly moving all my aviation workflows to my iPhone and iPad. I use SkyDemon (VFR flight planning), LogTen Pro (log book), AeroPlates (approach plates and Pooleys) and RocketRoute (IFR flight planning and flight plan submission).
Now I have added Aviation W&B Calculator to handle W&B calculations.
It’s very simple to set up. Just download the plane template for your aircraft and the empty weight from the POH and confirm the arms for the different stations from the POH and you’re good to go. For the Cirrus I fly, it shows take off and landing envelopes so I can calculate fuel required and fuel burn. It replaces and Excel spreadsheet and makes it easy to do W&B for every flight. I only wish it could do passenger weights in kilograms and fuel loads in litres but apart from that it’s perfect.