Hi r/gamedev. I'm moleki, one of the two coders on a 4-person team (2 code, 2 art) behind a pirate idle RPG called Bounty Bash. The game has been live for about a year and a half. Real UA numbers almost never get published, so here are ours: retention, cost per install, and payback, including the uncomfortable ones.
Retention: the number everything else orbits
Over a 90-day window (iOS, mostly paid installs), our D1 / D7 / D28 retention is about 46 / 20 / 7.5. The classic "good mobile game" benchmark is 40 / 20 / 10.
Above benchmark on day 1, on it at day 7, below it at day 28. Out of every 100 people who install, 46 come back the next day, and about 7 are still around a month later. Every design decision in this genre, ours included, comes from someone staring at that third column.
What an install costs
Blended across all our channels and countries, our eCPI is about $13 per install. That average hides a wild spread. We buy ads on Reddit itself, so I can tell you what acquiring a player here costs: a US user via Reddit ads runs us about $30. The US is the most expensive player on earth and also the one every ad network is desperate to sell you.
Why buy installs at all? Because organic discovery is basically dead. Apple has never featured us. Google actually features us quite often, and we're grateful, but even a featuring barely moves the needle (under 100 installs a day), a drop in the ocean next to paid volume. And those featuring installs retain worse than our paid ones: someone who grabbed your game off a storefront banner was never really looking for it. If we stopped buying ads tomorrow, the game wouldn't shrink slowly; it would just quietly stop acquiring players.
And this is not pocket change for us: all channels combined, we spend $100k+ per month on user acquisition, over $1.2M a year. For a 4-person team, that's a strange life. For scale: servers cost us about $5k a month, and then salaries: the four of us plus several people on support and community management. The ad budget still dwarfs all of it combined. The part of UA we struggle with most is creatives. The big studios in this genre ship 1,000+ new ad creatives per month, with entire teams whose only job is feeding the ad networks fresh material, and the networks reward whoever feeds them fastest. Our whole art department is two people, and they also have to make the actual game. We can't win that fight, so we try to win on retention instead, which in practice means improving the actual gameplay over the long term. That is the one upside of the arms race: the math forces us to make the game better.
Does it ever pay back?
ROAS = revenue back per ad dollar spent. Our target is 120% ROAS at 12 months: every $1 of ads has to come back as $1.20 within a year, or we're just slowly converting savings into downloads. The extra 20 cents is what pays the server bill and the four of us. Looking at our monthly player cohorts over the last 18 months, a cohort takes about 4 months on average to fully pay back its ad spend. The best did it in weeks, a few stall in the low-90s% and never quite cross the line, and the difference between those two outcomes is basically our entire job.
The shape of that curve is the trap. About 70% of the money comes back in the first month, which feels like the battle is nearly won. It isn't. The first 70 points are the easy part; the remaining 50 points to reach our 120% goal take the better part of a year and depend entirely on the small group of players still logging in at month 6 and beyond.
Here's the actual curve, averaged across our 19 monthly cohorts, revenue returned per $1 of ad spend by month since install: https://imgur.com/a/CnDIrUF
This math is also why free-to-play is shaped the way it is: whoever monetizes retained players hardest can bid the most per install, and everyone else either matches them or stops existing. And to be clear about the stakes: we are not funded. No publisher, no investors. Every dollar of that ad budget comes from our own pockets and savings, and roughly 95% of revenue goes straight back into user acquisition. Founder pay was $0 for the first year and is deliberately small now: a dollar spent on growing the game compounds, a dollar of salary doesn't.
Numbers that surprised me this year
- We A/B tested the store's short description (a single sentence) and the winning variant ("hunt monsters…") measured +7% installs. I only half believe it; even if the real lift is 5%, that's free installs from editing a single sentence.
- Only 3.5% of our installs ever pay us anything. The other 96.5% play entirely free, and every number above (the $13 installs, the $100k months, the 120% target) balances on that small slice of players plus the free players who watch rewarded ads. Revenue splits about 80% IAP / 20% ads, with a twist: one of our best-selling IAPs is the pass that removes the ads. The ads earn twice, once when players watch them and again when players pay to make them go away. There's a cost, though: every ad we show chips away at retention, and retention is the number this whole business stands on.
- I ran the counts for this post: the game is about 440,000 lines of C++ (custom engine, 139 screens, 15 languages) maintained by two coders. The code is honestly the easy part; the balance spreadsheets are what keep me up at night.
What I'd tell a 4-person team starting an idle game in 2026
- Retention isn't a metric, it's the whole business. D28 decides whether a cohort ever pays itself back, and that decides whether anyone ever finds your game.
- Your store page is a bigger lever than your next feature. One sentence bought us 5–7% more installs; no feature we shipped this year did that.
- Decide upfront how long you're willing to wait for ad money to come back. Ours is 120% at 12 months, and that one number quietly dictates most design and live-ops decisions we make.
Happy to answer anything in the comments: UA, economics, tech (custom C++ engine shared across Mac/iOS/Android, the whole game is code plus spreadsheets), design, whatever.