Everything in Theodia.

A short tour of what the app does — what ships in the box, what installs on demand, and what's optional.

Two ways to read

Theodia is built for however you approach the text. Pick the mode that matches your mood — or switch between them mid-session.

  • Focus mode — read like it's a brand-new physical Bible. Clean page, generous margins, small verse numbers that stay out of the way, and text laid out in paragraphs rather than one-line verses. No highlighting, no links, no buttons — just the text, uninterrupted. Perfect for devotional reading, public reading, memorization, or when you want the Scripture to feel like a book instead of a database.
  • Study mode — bring out the biblical scholar in you. Every verse is a doorway: tap to open cross-references, compare translations, read commentary, or check the original language data. All the apparatus is one tap away, and everything is still fully offline.

Read the Bible, fully offline

Theodia's whole reason for existing: an honest, fast, ad-free Bible reader that works the moment you open the app, with no network connection, no login, and no subscription.

  • Nine Bible translations bundled in the app. Open the app on a plane, in a basement, on a phone you bought used with no SIM card — the bundled translations are already there, and the reader is instant.
    • Public domain: KJV, KJV with Strong's numbers (KJVx), WEB.
    • Modern English: BSB (Berean Study Bible).
    • Translation-oriented: ULT (UnfoldingWord Literal Text), UST (UnfoldingWord Simplified Text).
    • Hebrew interlinear: OHGB (Open Hebrew Greek Bible) with Strong's-aligned data.
    • Transliteral Bible: TRLIT, TRLIT with Strong's (TRLITx).
  • Install more from the in-app catalog. If you want a translation we don't bundle (or a newer revision of one we do), the Resources screen pulls it straight from a GitHub release. No account, no store transaction — you point the app at a public release tag and the file downloads into the app's private storage.
  • Parallel Bible view. Read two translations side by side, verse by verse. Useful for translation comparison or for the literal-vs-dynamic tension (ULT next to UST, KJV next to BSB, etc). The pairing is yours to set — pick any of the in-app translations.
  • Compare any verse across every translation. The Compare screen lays out a single verse across all installed Bibles in one view.

Study, with the tools built in

Theodia isn't a reader with study tools bolted on. The same offline-first design extends to the apparatus — commentaries, lexicons, cross-references, morphology — so the study flow works the same way on a flight as it does at your desk.

  • Two commentaries, bundled (Scholar mode). Matthew Henry's complete commentary and the AIC (AI Generated Commentary) ship with the app. Tap any verse to see Henry and AIC on it, instantly, offline.
  • Strong's-aligned lexicon, bundled (Scholar mode). Look up any word by Strong's number, by English gloss, or by tapping it in the interlinear view. The bundled TRLIT (Transliteral Bible) lexicon covers Hebrew and Greek entries with definitions, transliterations, and parsing data. Additional lexicons are available from the in-app catalog.
  • Cross-references for every verse (Scholar mode). The cross-reference database is the same one the project was built around from the start. Tap a verse, see the related verses; tap a related verse, see its related verses. The graph is dense and worth getting lost in.
  • Morphology and word data on the original languages (Scholar mode). The Hebrew and Greek source text ships with parsing data, so tapping a word in OHGB or TRLIT shows its part of speech, root, tense, voice, mood — the things pastors and language students need.
  • Focus Mode for distraction-free reading. A clean single-bible view that strips the chrome and leaves the text. Tap-and-hold a verse to bring the menu back.
  • Devotional library, offline. A classic devotional bundled — Smith's Believer's Daily Remembrance — with a calendar-style picker so you can read today's entry or jump to any date in the year.

Encyclopedia, built in and expandable

Theodia ships with a full biblical encyclopedia right in the app, and you can add more classic reference works from the in-app catalog. Every article is searchable, readable offline, and connected to the rest of your library.

  • Kitto’s Cyclopedia of Biblical Literature (KIT), bundled. Thousands of articles on people, places, events, and topics — available the moment you install the app, with no download or account required.
  • Search across encyclopedias. Look up any entry by name and jump straight to the article. Results work across every installed encyclopedia from a single search screen.
  • Linked articles and verses. Encyclopedia entries link to related articles and to the Bible passages they cite. Tap a link to open the entry or the verse without losing your place.
  • Install more from the catalog. Download additional classic encyclopedias — including McClintock and Strong, Hastings’ Dictionary of the Bible, the International Standard Bible Encyclopedia, and more — straight from the in-app resource catalog under Settings → Manage Resources.

Dictionaries for deeper word study

In addition to the bundled Strong's-aligned lexicon, Theodia lets you install and search classic Bible dictionaries. Look up names, places, doctrines, and theological terms without leaving the verse you're reading.

  • Strong's-aligned lexicon, bundled. Tap any Hebrew or Greek word in the interlinear view to see its Strong's number, gloss, transliteration, and parsing data.
  • Bible dictionaries. Add reference works from the in-app catalog the same way you add Bibles, commentaries, and encyclopedias.
  • Verse-aware lookups. In Study mode, open the dictionary panel for any verse to see relevant entries drawn from your installed dictionaries.
  • Cross-linked with everything else. Dictionary entries link back to verses, encyclopedia articles, and lexicon entries so you can follow a word through every layer of the library.

Search, the way you'd expect

  • Full-text search across every translation at once. Type a word or a phrase; the results screen shows the hits grouped by book and chapter, with the matching verse in context.
  • Filter by translation. If you only want to search the Greek word "agape" inside the BSB interlinear, you can.
  • Jump to the verse from the result. One tap and you're in the reader, with the verse highlighted.

Bookmarks, highlights, and notes — all yours, all local

  • Bookmarks with folders (Standard and Scholar modes). Tag a verse, file it in a folder ("Sermon Prep," "Comfort," "Wedding readings"), recall it later. Long-press a bookmark to move it between folders, and create new folders from the Bookmarks tab.
  • Highlights with per-color tagging (Standard and Scholar modes). The app ships with a small palette; the highlights stick to the verse and survive a chapter reload.
  • Bible notes and study notes, with two different scopes (Standard and Scholar modes). A Bible note is anchored to a specific verse; a study note is a free-form document that lives in a notebook you organize yourself. The two are deliberately separate so the verse-anchored notes don't drown the notebook, and the notebook doesn't lose track of which verse a thought came from.
  • Export everything (Standard and Scholar modes). Bookmarks, highlights, and notes can be exported to a file or to the clipboard. Bring them into your sermon-prep workflow, your OneNote, your Obsidian vault, your email.
  • No cloud, no account, no sync. The data lives on the device. The privacy policy explains why we made that choice.

Personalize the reading

  • 27 interface languages. English, Simplified Chinese, Traditional Chinese, Spanish, Hindi, Arabic, Portuguese, Russian, German, French, Italian, Polish, Ukrainian, Romanian, Korean, Filipino, Vietnamese, Japanese, Indonesian, Dutch, Hebrew, Thai, Turkish, Greek, Czech, Swedish, and Danish. The Bible translation language is independent of the UI language, so you can read Lithuanian Scripture with a Spanish interface, or English Scripture with an Arabic interface.
  • RTL support, automatic. Open an OHGB (Hebrew) Bible and the reader flips to right-to-left; the parallel view, the verse numbers, the highlights — all of it. Switch to an English Bible and the chrome flips back.
  • Themes. Standard and dark. The theme follows the system setting or your manual choice, whichever you prefer.
  • Font size controls. From the Settings screen. The reader respects your device's accessibility text-size setting on top of that.
  • Default Bible and parallel Bible (Standard and Scholar modes). Set which translation opens when you tap "Bible," and which one shows up alongside it.

Three user modes

Theodia lets you choose how much of the app to show. Pick the mode that fits your study habits — or switch anytime in Settings.

  • Reader mode — the text, nothing else. A clean Bible reader with no bookmarks, highlights, notes, or study tools. Ideal for devotional reading, public reading, or anyone who wants Scripture without apparatus.
  • Standard mode — read and study. Everything in Reader mode plus bookmarks, highlights, notes, parallel Bibles, TTS, and quick commands. This is the default mode and covers most Bible study needs.
  • Scholar mode — every tool unlocked. Everything in Standard mode plus commentaries, lexicons, word-level morphology, dictionary lookups, the AI assistant, developer settings, and the ability to install additional resources from the catalog.

Text-to-speech, built in

Listen to the Bible, commentaries, and books aloud — in Standard and Scholar modes. TTS works offline using your device's built-in voices, with a stop button and per-translation voice selection.

  • Read aloud on demand. Tap the speaker icon in any reader to start TTS at the current verse. A stop button lets you pause instantly.
  • Pick a voice per translation. Choose a different TTS voice for each Bible so English and Hebrew texts sound distinct.
  • Background audio. TTS continues when you switch apps or lock the screen (iOS), so you can listen while walking, driving, or doing chores.
  • Optional parenthetical reading. A setting lets you include or skip text inside parentheses, so chapter headings and cross-references don't interrupt the flow.

Built for tablets, not just phones

Theodia recognizes when it's running on a tablet (any screen where the shorter edge is 768dp or larger) and adapts the layout to use the extra space. Read the full tablet feature list →

  • Side-by-side study panels. In Study mode on a tablet, cross-references, commentary, compare, lexicon, and dictionary panels slide in from the right as persistent sidebars instead of covering the full screen. You read the passage on the left and the study tool on the right, without losing your place.
  • More generous margins and larger touch targets. Books, chapters, and reader screens all get wider padding, larger verse numbers, and bigger buttons so the app feels native to the form factor.
  • Focus mode gets room to breathe. The clean page layout centers the text with comfortable line lengths and paragraph spacing — more like a printed page, less like a phone screen.

The AI assistant (optional, Scholar mode)

Theodia includes an AI assistant named Theophilus that can read alongside you, answer study questions, and (with your permission) operate the app on your behalf. The AI features are entirely optional — Theodia works exactly as described above with the AI turned off, and the AI does not phone home. Learn more about Theophilus →

  • Theophilus, your study companion. Theophilus can look up any verse, summarize a chapter, pull every cross-reference for a passage, look up a word in the lexicon, create a bookmark from a conversation, and write a study note for you — all by asking in plain language.
  • Tool-using, not just chat. Unlike a chatbot bolted on top of a Bible website, Theophilus is wired into the same data layer the rest of the app uses. When you ask "what does the Greek say in Romans 8:28," it actually queries the lexicon, not a cached string.
  • You choose the model. The app talks to any OpenAI-compatible endpoint — OpenAI, Anthropic (via a proxy), a self-hosted llama.cpp, an Ollama server, or a Bible-specialized model — and you configure the endpoint, the model, and the API key in Settings. There is no Theodia-branded model you have to subscribe to.
  • Your API key stays in the secure enclave. The key you paste into Settings is stored in the iOS Keychain or Android Keystore, used to authenticate the requests you send, and never logged or mirrored.
  • Multi-conversation history with projects. Organize chats into named projects ("Sermon on Romans 8," "Genesis study group," "Personal devotions"), rename them, archive them, and switch between them from the chat drawer.
  • You stay in control. Theophilus never deletes a note, never removes a bookmark, and never changes a setting without you confirming. The tool surface is deliberately conservative.

Privacy and control, by default

Theodia's data architecture is the same architecture the user experiences: nothing leaves the device unless the user explicitly turns on a feature that needs it.

  • No account. No tracking. No analytics. The app does not collect usage data, does not include a crash reporter that phones home, and does not include an advertising SDK. The iOS privacy manifest declares NSPrivacyTracking: false.
  • All your data is on your device. Bookmarks, highlights, notes, AI conversation history, downloaded Bibles, downloaded models, and the GitHub PAT or AI API key you may have added — all of it lives in the app's private storage or the platform's secure enclave.
  • Export and delete, granularly. You can export bookmarks, highlights, and notes; you can delete them per-category; you can uninstall the app and the data goes with it.
  • Read the full privacy policy for the disclosure.