We built it with React Native, Firebase and RevenueCat, plus a Next.js website. Here's what mattered most when building a content-and-subscription app for a Spanish-speaking audience.

Write for Spanish first, not as a translation

Apps that start in English and "add Spanish later" usually read like it. For Mi Paz we treated Spanish as the source language:

• Copy is longer. Spanish strings often run noticeably longer than English. Buttons and cards were designed with room to spare, and we tested with the longest real strings, not placeholder text.
• Dates, numbers and plurals go through proper i18n formatting (Intl APIs) instead of string concatenation.
• Tone matters. Devotional content has to feel warm and natural; that's an editorial decision, not an engineering one, so the content pipeline keeps text editable without an app release.

Content that updates without app-store releases

Daily content can't wait for app review. Reflections, verses and prayers live in Firebase, structured by date and locale:

devotionals/{locale}/{yyyy-mm-dd} -> { title, reflection, verse, prayer }
weeklyVerses/{locale}/{isoWeek}   -> { reference, text }

The app caches the next few days locally so it works on a weak connection (common for users on prepaid mobile data) and simply refreshes when online.

Subscriptions with RevenueCat

Handling App Store and Google Play billing directly means two receipt-validation systems, renewal edge cases and a lot of server code. RevenueCat gave us:

• one entitlement (premium) checked the same way on iOS and Android;
• a free-trial flow (Mi Paz offers a 7-day trial) without writing our own receipt logic;
• a single dashboard for renewals and churn.

The app only asks one question at runtime: does this user have the premium entitlement? Everything else lives in RevenueCat's configuration.

A companion website that actually helps

The Next.js site at mipaz.app is not just a download page: it explains the content, answers FAQs in Spanish, and is server-rendered so it's indexable and shares cleanly in WhatsApp, the main sharing channel for much of Latin America.

Lessons for faith, wellness and content apps

1. Make the daily habit effortless: one tap from notification to today's content.
2. Keep content editable outside the app binary.
3. Use a subscription layer like RevenueCat unless billing is your core business.
4. Design for the language your users actually speak, from the first wireframe.

Mi Paz is live on the App Store and Google Play. If you're building a content, faith or wellness app for Spanish-speaking users, we'd be glad to help. We're I Plus T Solution, a software and AI development team in Gurugram, India: https://www.iplust.in/