Mobile app backend hosting cost calculator

Most mobile apps require a backend infrastructure, e.g. to retrieve data, manage app content or to send push notifications to app users. You can either build your own backend in the cloud, or you can choose for a hosted mBaaS (mobile backend as a service) solution. Either way, it is difficult to calculate the overall cost, since it typically depends on number of app users, but also number of requests etc. That's why I have crafted a backend cost calculator, that I am happy to share with you.

Calculate bandwidth and backend cost for your mobile app
Bandwidth per user
Bandwidth usage per user for first session (initial content download) KB You can measure the bandwidth usage of your app using a proxy tool (e.g. Charles), or view e.g. the cellular data usage per app on iPhone under Settings/Cellular.
Bandwidth usage per user for consecutive sessions (content updates) % of first usage
Bandwidth usage per user for consecutive sessions (content updates) KB Estimate or through actual measurements, consecutive usage is typically lower since apps must only download incremental now content/data.
Bandwidth per active user per month
Number of sessions per user per month E.g. If your users use your app on average once a day, this number is "30" (30 sessions per user per month).
Total bandwidth per user per month KB
Total bandwidth usage per month
Total new app users per month New active users per month (app downloads that actually launched app).
Total active app users per month Total active users per month.
Total bandwidth per month (Kbytes) KB
Total bandwidth per month (Gbytes) GB
Bandwidth cost
Price per GB /$ Cost per GB data transfer on your cloud (e.g. Amazon), mBaaS provider and/or CDN.
Bandwidth cost per month /$
Backend (API) requests cost
Number of backend requests per user session E.g. if your app calls a backend (API) on average 10 times per user session, this number is "10".
Total number of backend requests per month
Peak hours per day If your app is used by users around the world, this number is "24". If your app users are primarely from one timezone and typically using your app during daytime, this number is "12" (meaning 12 active hours per day).
Total number of backend requests per hour
Total number of backend requests per second
Cost per 1 million backend request /$ Cost from your mBaaS provider. This cost is 0 in case you host your own servers (see below), e.g. VM's in the cloud.
Cost per month for backend requests /$
Push notification cost
Cost per 1 million users for push notifications (per month) /$ Cost from your mBaaS or mobile marketing provider. Note that Apple/Google do not charge for sending push notifications.
Cost for push notifications /$
Backend server dimensioning (in case you manage your own backend)
Loadbalancers
Max. requests (hits) per second per loadbalancer Estimated maximum load your load balancers can handle (if you have any).
Number of loadbalancers
Cost per loadbalancer per month /$ Cost from your cloud provider per LB per month.
Total cost per month /$
Web/API servers
Max. request (hits) per second per web/API server Estimated maximum load your backend/API servers or web servers (in case of web apps) can handle, e.g. "20" could be a realistic number for a simple VM with 1GB RAM and 1 CPU core.
Number of web/API servers
Cost per server per month /$ Cost from your cloud provider per server per month.
Total cost per month /$
Database servers
Max. requests (hits) per second per DB server Estimated maximum load your DB servers can handle, expressed in number of API requests (hits). So if you have 10 API request per second, and each API requests performs 10 queries, this would mean 100 queries per second.
Number of DB servers
Cost per server per month /$
Total cost per month /$
Total server cost per month /$