I have been working on an app for roughly 3.5 years. The app has one main feature, finding recently opened up street parking, and it does this by looking at user movement data and intelligently pinpointing where they got in their car and drove off from, meaning that's the new empty spot.
This took a mountain of work. Not just coding, but driving around, bugging friends to test it out, etc.
I even did an initial launch a 1.5 years ago:
1. I got 1000 users at roughly $2.5 (ad spend) per download so its something people cared about
2. 70% of my users would open the app once a day to check for open parking
3. My app only picked up parking 10% of the time, meaning from my 1000 users, I only got 100 spots a day
Ultimately item 3 killed my launch, 10% was too low a rate. Users would open the app and wouldn't see any spots. They slowly dropped off.
Instead of giving up, I continued working on it. Since then, I did major changes to the algorithm and reached a parking detection rate of 40%. This means 400 spots from 1000 users per day. This could result in 3-8 spots showing up anytime users open the app--which would finally make it useful. Personally, I can see this catching on.
---
Anyway, I recently met someone who is pretty smart. I'm a tech guy, he's a data-science/marketing guy, but just one of those overall sharp people that could wear multiple hats. He's also got a lot of good credentials. He's a bit arrogant but that's ok--we work well together.
He and I discussed him joining as a co-founder and applying to YC. Initially my hard limit was 30%, but he wants 40%. I'm conflicted now. On one hand, I want a very smart, potentially game-changing cofounder. On the other hand, I feel my 3.5 years of hard work mean something, and I should have a significantly larger piece of the pie because of that.
What is an equity split that would make sense?
He's a bit arrogant but
In any relationship, whatever irritates you at the outset has the potential to become a real source of resentment later, so be clear about where your boundaries are.
A lot depends on how much work this potential partner is proposing to put in before bringing in the big bucks and potentially cashing out. But putting all those meta considerations aside, if you want 30%, he wants 40%, and you really feel he has something you don't which would be hard to find elsewhere, 33 1/3% seems like the natural inflection point.
reply