> ## Documentation Index > Fetch the complete documentation index at: https://docs.summerengine.com/llms.txt > Use this file to discover all available pages before exploring further. # Make a single-player or mobile game > The Summer pieces behind a single-player or mobile game: the player's Summer account, items that follow them, a Sparks shop, analytics and publishing, with no server to run. A single-player game doesn't need a server to feel connected. With Summer, every player already has an account. Items they unlock or buy belong to that account, so they survive a reinstall and follow the player to a new device. Your shop runs through Summer's own checkout, and analytics show you what players do. This page shows how the pieces fit together. ## The pieces you need A shop where players buy items with Sparks through Summer's checkout. Skins and themes the player owns and equips. Events from your game in your analytics. Sell the game itself, or accept tips from players. Save on the device, and add a server when saves should follow the player everywhere. Show a public top 50; a Summer server records the scores. Ship it to summer.games. ## How it fits together The single-player loop: the player plays on their device, unlocks items owned by their Summer account, buys more in a shop through Summer checkout, and the creator learns from analytics. The single-player loop: the player plays on their device, unlocks items owned by their Summer account, buys more in a shop through Summer checkout, and the creator learns from analytics. The game runs on the player's device, and the player is signed in to Summer. The items they own come from their account, so your game unlocks content from what they really own. When they buy something, Summer shows its own checkout over the game, and your game unlocks the item once Summer confirms it. Your analytics show which levels players finish and what they buy. ## Plan my game I'm making a single-player game in Summer. Read my project and plan how to add these Summer features with these skills, in this order; if you don't have them installed, find them in the Summer library: 1. `save-load`: progress saved on the device, with a versioned save format. 2. `in-game-purchases`: a shop that sells items for Sparks through Summer's checkout, unlocking only what the player owns. 3. `summer-analytics`: events for the moments I care about, such as a level finished or an item bought. 4. `export-and-ship`: get the game ready to publish. For each step, tell me what changes in my project and what I'll see when I test it. Don't change any files yet. ## Build the signature features ### A shop that unlocks for real In my Summer project, add a shop that sells \[ITEMS] for Sparks. Use the Summer `in-game-purchases` skill; if you don't have it installed, find it in the Summer library. * Buying opens Summer's own checkout over the game. * The game unlocks an item only once the player owns it, so it survives a reinstall and works on their other devices. * If the shop isn't available, hide it and keep the game playable. Read my project first and tell me where the shop fits. Then tell me what I can only check once the game is published. ### Learn what players do In my Summer project, send analytics events for \[MOMENTS, for example "level started, level finished, item bought"]. Use the Summer `summer-analytics` skill; if you don't have it installed, find it in the Summer library. Events must never slow down or block the game. Read my project first and tell me which events you'd add and where, before you change anything. *** Does this not help you? [Reach out on Discord!](https://discord.gg/summerengine) This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.