--- title: I Built an App Nobody Asked For | daily.dev description: An indie developer shares the story of building HerBattery, a private offline mobile app designed to help partners track menstrual cycle context in... canonical: https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: I Built an App Nobody Asked For | daily.dev og:description: An indie developer shares the story of building HerBattery, a private offline mobile app designed to help partners track menstrual cycle context in... og:url: https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql og:image: https://api.daily.dev/og/posts/cewqCRkQL.png og:image:alt: I Built an App Nobody Asked For og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # I Built an App Nobody Asked For **[Medium](https://daily.dev/sources/medium_js)** · 6 min read · 0 upvotes · 0 comments ## Summary An indie developer shares the story of building HerBattery, a private offline mobile app designed to help partners track menstrual cycle context in relationships. Built without market validation or user demand, the app prioritizes privacy by storing all data on-device with no cloud or AI. The post reflects on the challenge of building for an uncategorized problem, the ethical design decisions around avoiding surveillance, and the surprise of early adoption driven largely by women sharing it with their partners. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Young people are outsmarting period tracking apps](https://daily.dev/posts/young-people-are-outsmarting-period-tracking-apps-vdqslxqvy) · Mozilla · 35 upvotes · 6 comments - [My most popular application](https://daily.dev/posts/my-most-popular-application-0rfpxbnwj) · Lobsters · 0 upvotes · 0 comments - [Your period tracking app has been yapping about your flow to Meta](https://daily.dev/posts/your-period-tracking-app-has-been-yapping-about-your-flow-to-meta-uifgigkgp) · Hacker News · 0 upvotes · 0 comments --- Tags: [#mobile](https://daily.dev/tags/mobile), [#privacy](https://daily.dev/tags/privacy), [#flutter](https://daily.dev/tags/flutter) [View this post on daily.dev](https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"I Built an App Nobody Asked For","url":"https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql"},"datePublished":"2026-07-18T07:33:17.261Z","dateModified":"2026-07-18T07:34:09.398Z","description":"An indie developer shares the story of building HerBattery, a private offline mobile app designed to help partners track menstrual cycle context in...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/383b5e6ae1d6a95c4b602ff10269c10b?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/383b5e6ae1d6a95c4b602ff10269c10b?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Medium","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Medium","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/medium","url":"https://daily.dev/sources/medium_js"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/i-built-an-app-nobody-asked-for-cewqcrkql","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"mobile,privacy,flutter","timeRequired":"PT6M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Medium","item":"https://daily.dev/sources/medium_js"},{"@type":"ListItem","position":3,"name":"I Built an App Nobody Asked For"}]} ```