Shopping without paper

My son Derek has developed a new shopping app called "CleverList."
We bought one last night because I'm always shopping and he's my son and I wanted to go on record as spending the $2 for one of the original apps.
Besides, Derek just might become rich and famous with a pool at his big house someday and we want to be visitors who are admitted to the premises.
Marc and I sat down to check the options out.
It's actually pretty well thought out. There's a place to list the things one usually buys like bread and milk and eggs and as you repeat the shopping exercise week after week, the app tracks your movements and creates a pattern for you.
Eventually your iPad or smartphone can get in the car, start the engine and do the shopping without you. (Not really, but wouldn't it be nice?)
I think the idea is a sound one and something that would eventually save time and paper.
There's only a few problems I can see from the cheap seats.
I have different lists for different stores.
I started explaining this to Marc as he tried to keep up with the input.
"I only buy eggs and roasts and those little round cheeses wrapped in red wax at Costco. I never buy my fruit or bread there. The bread's old and the quantity of fruit I get is too much for us," I explained.
"At Smith's, I get the sugar-free ice cream we like, the frozen orange juice for a good price, the super lump crab meat and milk that tastes good. I never buy my vegetables there because I can't find the petite corn or peas. I do buy the double fiber with honey bread unless I've splurged this week and bought some at Great Harvest."
I drew a breath.
"At Fresh Market or Macey's, I pick up fresh fruit and vegetables and frozen vegetables. I can find the tortellini I like there but not the chicken in little packages of two breasts each."
Marc was having a hard time keeping up.
"When Smith's sends out their gold coupons, I shop there for all of the things I can save money on, like butter, cheddar and cottage cheese. When Costco releases their coupon book, I buy toothbrushes and dish detergent and rice and flour, not soup because I don't like the kind they carry."
Marc stopped typing.
"Well? Aren't you putting this all down," I said.
He sighed.
"I think you're exceeding the program limits," he said. "And you don't have a smartphone or iPad so how are you going to do this?"
Oh, yeah. That will definitely make it harder.
I guess, for me, it's back to pen and paper, huh?