I launched my first app in India with zero knowledge of user acquisition costs, burned through 40,000 rupees on Facebook ads in two weeks, and acquired exactly 47 downloads. That’s 851 rupees per install, or about 7 USD, for an app that charged 49 rupees upfront. I lost money on every single user. I didn’t know how to calculate mobile app user acquisition cost in South Asia, and it nearly killed the project before it started. Three years later, after running campaigns across India, Sri Lanka, and Bangladesh, I understand the mechanics well enough to help you avoid that mistake.
Most indie developers treat UAC like a mystery. They throw money at Facebook ads or Google App Campaigns, watch the installs tick up, and hope something sticks. Then they’re shocked when the numbers don’t work. The real problem is not the cost per install itself. It’s that they never built the math backwards from revenue. If you don’t know what a user is worth to you, you can’t know if you can afford to acquire them. I’m going to show you the framework I use now.
Why most indie developers get UAC completely wrong
The biggest mistake I see is conflating downloads with paying users. When you buy a Facebook ad, you’re paying for clicks and installs from people who might never launch your app again. App store listings, organic growth through word of mouth, and ASO (app store optimization) bring users at zero direct cost, but they’re invisible in the paid channels. I spent my first 6 months only tracking ‘installs’ and wondering why my conversion rates looked fine on paper but my revenue looked terrible. Then I realized I was comparing paid installs (lower quality, higher intent to check something out immediately) with organic installs (often accidental, low engagement). They’re not the same user.
The second mistake is ignoring retention entirely. A user who costs you 300 rupees but deletes your app after one day is infinitely expensive. A user who costs you 500 rupees but stays active for 60 days and makes three in-app purchases is the best deal you’ll ever get. I track my apps by cohort now, meaning I know exactly what each group of users acquired in a given week is worth 7 days later, 30 days later, and 90 days later. That’s the only number that matters for deciding if a campaign is actually working.
The basic formula and the numbers that actually matter
Here’s the simplest version: UAC = Total Ad Spend / Number of Installs. If I spend 10,000 rupees and get 100 installs, my UAC is 100 rupees per install. But that number is useless without context. The only metric that matters is Lifetime Value (LTV). If each user is worth 80 rupees to you over their lifetime (one-time purchase, or in-app ads, or subscriptions), then 100 rupees UAC is a losing bet. If each user is worth 500 rupees, then you’re printing money. I use a simple spreadsheet: ad spend, installs, cost per install, and then I multiply by my actual LTV from the app store data. That one multiplication tells me if a campaign is viable.
To calculate LTV, I pull revenue reports from Google Play Console and Apple App Store Connect monthly. I divide total revenue by total active users in that cohort over the period I’m tracking. For my current app, a user acquired through paid ads is worth about 240 rupees over 30 days (a mix of one-time purchases and ad revenue). My target UAC is therefore 80 rupees or less to maintain a healthy 3:1 LTV:UAC ratio. Anything above that, I kill the campaign immediately. I learned this after six months of running ads with a 5:1 ratio and wondering why I was breaking even instead of scaling. The math was right, but my payback period was too long and I ran out of capital.
How to calculate mobile app user acquisition cost for iOS vs Android
iOS and Android have wildly different cost structures, and most founders from South Asia don’t account for this. Apple’s App Tracking Transparency (ATT) policy, introduced in 2021, means you can’t target iOS users with the same precision as Android. This drives up costs. On Android, Facebook can track user behavior through the Google Play Store SDK. On iOS, you’re blinded. I’ve seen iOS UAC run 40 to 60 percent higher than Android for the exact same campaign. That’s not a rounding error. If Android UAC is 100 rupees, iOS might be 160 rupees.
For my current portfolio, I run separate budgets for iOS and Android and track them separately in my spreadsheet. I allocate 70 percent of budget to Android and 30 percent to iOS because the returns are better, even though the iOS user base has higher willingness to pay. This is a business decision, not a technical one. I set a hard rule: iOS UAC can be 50 percent higher than Android UAC because iOS users convert at roughly double the rate. If that ratio breaks, I pause iOS and double down on Android. I check this math every two weeks. Google App Campaigns and Facebook Ads Manager both allow you to set separate budgets by platform, so use that feature.
One more thing on iOS: attribution is messier. Apple’s SKAdNetwork replaced IDFA, which means your ad platform can’t see the full conversion funnel anymore. This makes it harder to tie revenue directly to installs. I’ve shifted to working backwards from App Store data instead of trusting the ad platform’s attribution. Every week, I check the cohort data in App Store Connect, see how much revenue each cohort generated, and divide by install count. That’s my real number. The ad platform’s dashboard is entertainment.
Real benchmarks from my apps in the South Asian market
I’ve run campaigns for five apps across India, Sri Lanka, and Bangladesh since 2023. Here are the actual numbers I’ve seen. For a simple puzzle game with ad revenue and IAPs, Android UAC ranged from 60 to 140 rupees depending on the season. November through January is expensive (everyone else is advertising for the holiday season), so UAC jumped 35 to 45 percent. February through May is cheaper, down 25 to 40 rupees. iOS UAC for the same game was 220 to 280 rupees. LTV was roughly 320 rupees for Android cohorts and 850 rupees for iOS cohorts. The math worked because iOS users were willing to spend, even though they cost more to acquire.
For a productivity app with a 399 rupee subscription (no free trial), Android UAC was consistently around 80 rupees, and LTV stabilized at 1,200 rupees over 180 days (assuming 60 percent of paying users stuck around for six months). That’s a 15:1 ratio, which is unsustainably good, but the category has low volume. I only acquired 200 paying users per month from ads because the audience is small. iOS UAC was 280 rupees for the same app, but LTV jumped to 2,100 rupees because iOS users are heavier spenders. This app actually scales better on iOS despite the higher upfront cost.
Utility apps in Sri Lanka (currency converters, calculation tools) have the worst unit economics. UAC is similar to the puzzle game (80 to 120 rupees), but LTV is brutal: 40 to 80 rupees because users install, use once, and leave. I stopped advertising these apps. They’re not acquisition-friendly. Word of mouth and organic growth work better. This is the hard lesson most developers skip. Not every app should be acquired. Some are just too low-revenue to make ads worthwhile.
How to know when your UAC kills your business model
If your LTV to UAC ratio is below 2:1, you’re losing money when you factor in operational costs. Ads, payment processing fees, infrastructure, support, and your own time all eat into the margin. I use a conservative 4:1 threshold now. If I can’t hit that ratio, I don’t scale the campaign. For subscription apps, this is even stricter because you need a payback period of under 90 days to stay solvent before churn inevitably kicks in. Most users cancel subscriptions within 90 days if they haven’t seen ongoing value. Your UAC has to be low enough that you recover the cost before they leave.
The second kill switch is payback period. If your UAC is 200 rupees and the user generates 10 rupees in revenue on day one, you need 20 days to break even. If the user becomes inactive on day 15, you never break even. I calculate this by looking at cumulative revenue by day in cohort reports. If I’m not at 50 percent payback by day 10, the campaign is inefficient. I don’t need full payback by day 10, but the trajectory needs to be clear. App Store Connect and Google Play Console both show you revenue curves by cohort. Use them.
The third signal is absolute cost. If you’re spending more than 5,000 rupees per week on a campaign and the UAC is above your threshold, kill it immediately. Compound losses are lethal. I learned this by running a campaign for eight weeks, hoping the numbers would improve. They didn’t. I lost 40,000 rupees chasing a mirage. Now I set a hard budget limit of 2,000 rupees per week per campaign for testing, and I review results every seven days. If UAC is trending upwards, I pause and investigate. Sometimes it’s just a iOS vs Android mix shift that I can fix. Sometimes the audience is exhausted and I need to restart. Either way, I catch it early.
Track your UAC every single week. Set up a simple Google Sheet with columns for campaign name, ad spend, installs, UAC, LTV (pulled from the app store), and the LTV:UAC ratio. Add a row every Friday. If the ratio drops below your threshold for two consecutive weeks, pause the campaign. If it holds steady or improves, scale the budget by 25 percent and check again in another week. This is not set-and-forget. Your acquisition costs are live, and the market changes fast. Treat it like you’re playing a game where the rules shift weekly, because that’s exactly what’s happening.