Comparison

On‑Device AI vs Testify

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

On‑Device AI

Transform your device into a private AI assistant for meetings and complex tasks. Features include speaker diarization, live transcription, and specialized subagents for research, analysis, and writing. Control your AI via messaging apps, with options for 100% offline processing or cloud connectivity.

Highlights
  • Speaker Diarization for meeting transcripts
  • Real-time live transcription
  • Natural AI speech generation
  • Deploy specialized AI subagents
  • AI-powered web browser automation
  • Control AI via messaging apps
  • 100% offline processing option
Read full description

On-Device AI puts chat, listening, transcription, notes, and research in one private app for iPhone, iPad, Mac, and Apple Vision Pro. Your data stays on your device. Download a model once and keep working on a plane, on the subway, or without a signal. Chats, documents, recordings, and notes stay on your device. Online providers and web features are optional and work only after you enable them. ONE APP, YOUR WAY Open every workspace from a customizable Menu. Keep favorites under Pinned and everything else close by under Available. AI CHAT Chat with local or cloud models. • Run local models from families such as Gemma, Qwen, DeepSeek, and Mistral, or connect your own provider account • Browse, download, and manage models that fit your device, including ones for text, vision, reasoning, and tools • Drop in documents, images, and scanned PDFs; approve private on-device OCR only when a PDF needs it • Fork any conversation and compare several models on the same prompt • Let the model use tools for calculations, web requests, documents, Calendar, and Reminders, and review proposed changes before they apply • Create reusable Agent Profiles, then add AI Skills, MCP servers, and tools from one clearer Agent Workflows setup • Keep facts you repeat often in Global Memory LISTEN LIBRARY AND RSS FEEDS Read less, listen more. • Turn PDFs, Markdown, plain text, web articles, and scanned books into a listening queue • Scan photographed pages, correct the OCR the app runs on device, and keep each page with its spoken text • Follow sites through RSS, Atom, and JSON feeds, then send articles to Up Next • Choose Apple voices or local neural voices, follow along in the reader, and set a sleep timer VOICE NOTE, VOICE TYPING, AND TEXT TO SPEECH Speak instead of typing, and listen instead of reading. • Record and transcribe meetings, lectures, interviews, and quick ideas • Dictate with Voice Typing on Mac or the voice keyboard on iPhone and iPad • Transcribe with Apple Speech, Whisper, Parakeet, Nemotron, Qwen3-ASR, MOSS, and other engines • Turn text, or text captured from a photo, into audio with Apple voices, Kokoro, Supertonic, VoxCPM2, IndexTTS2, and other engines • Export transcripts as text, subtitles, or Markdown AI SEARCH AND AI BROWSER Research with a second pair of hands. • Search the web in a conversation and let the model read the results for you • Browse with tabs, profiles, history, and downloads, then ask your model to read, assist, or act on the page • Hand a task to the browser agent, watch each step, and take over whenever you want KNOWLEDGE AND TEXT NOTE Give your AI your own material to work from. • Add PDFs, text, Markdown, code, images, and website content to a private searchable library • Write and edit Markdown notes in the app • Import AI chats, voice notes, Text to Speech items, and AI Search results • Tune retrieval and index edited content again APP HELP Ask how a feature or setting works. App Help answers from a guide that ships inside the app, keeps help out of your saved chats, and points to the right settings. MADE FOR APPLE DEVICES • Native layouts adapt from focused navigation on iPhone to category sidebars on larger screens • Settings are grouped by purpose, including Voice Typing, Agent Workflows, Models & Storage, Privacy & Data, Memory, and—on Mac—Instant Messaging • Widgets for Listen, Voice Note, Text Note, and Quick Actions • Siri, Apple Shortcuts, App Intents, the Mac menu bar, and keyboard shortcuts you can customize • Apple hardware acceleration for supported local models • Browse chat, transcription, speech, and embedding models in one Model Library • Store models internally, on an external drive, or on a shared volume, with separate tools for cleanup and recovery • Interface in English, Dutch, French, German, Italian, Japanese, Spanish, Portuguese, and Traditional Chinese EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Testify

This app helps you conduct scientific experiments in your daily life. Define a hypothesis, track your results, and get clear, statistical explanations of whether your findings are significant. It supports various statistical tests and offers visual data analysis.

Highlights
  • Create experiments with hypotheses
  • Track daily results and notes
  • Automatic statistical analysis
  • Visual charts and confidence intervals
  • Plain-English result explanations
  • CSV import/export (Pro)
  • PDF report export (Pro)
Features
Read full description

Testify lets you run real experiments on your everyday life. Wondering if keeping your windows closed keeps your house warm? Curious whether wearing socks affects your productivity? Maybe you want to see if your sports team plays better if it is raining? Stop guessing and start testing. Set up an experiment with a hypothesis, track your results day by day, and let Testify crunch the numbers. The app automatically picks the right statistical test for your data — Chi-Squared for yes/no outcomes, or a Two-Sample T-Test for measurements — and tells you in plain language whether your results are meaningful or if you need more data. Features: - Create experiments with a hypothesis and a variable to test - Record trials with date, time, results, and optional contextual notes - Automatic statistical analysis with Chi-Squared and Welch's T-Test - Optional Bayesian view showing the probability one variant is better, with a 95% credible interval - Sequential analysis with a Pocock boundary so repeated peeking doesn't inflate false positives - Visual charts comparing your control and treatment groups, with a best-fit trend line for numeric experiments - Confidence intervals so you can see the range of possible effects - Post-hoc statistical power analysis - Sample size estimates that tell you how much more data you need - Plain-English explanations of your results — no stats degree required - Share polished result images with friends or social media - Daily reminders to log your data, with deep links straight to the experiment - Edit experiments and trials at any time, conclude or reopen as your investigation evolves - Track multiple experiments at once with a last-viewed summary card - Home screen widget showing your most recent experiment and a one-tap Add Trial shortcut - First-launch walkthrough to get you started quickly - Light and dark mode support Testify Pro (optional subscription): - Unlimited experiments - CSV import and export for your trial data - Multi-page PDF report export with charts, summary, and trial table Whether you're optimizing your daily routine, identifying patterns, or just settling a debate with yourself, Testify gives you the statistical tools to find out what actually works.

Screenshots

On‑Device AI4 screens
Testify4 screens

Verdict

The call

The clearest difference is rating: Testify at 5.0 against On‑Device AI's 4.4. On‑Device AI's advantage is ratings volume (162 vs 1) and device support (4 vs 2). On price, ads, in-app purchases and monetization model there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. On‑Device AI sells 4 in-app purchases, starting at $3.99 per month and Testify sells 1 in-app purchase, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Testify holds the better App Store score, 5.0 against 4.4. That said, the two scores are not equally well evidenced: On‑Device AI has 162 ratings behind it against 1, so its average is the more settled of the two.

Scorecard4 real differences · 6 level
On‑Device AI versus Testify: the parameters behind the verdict, then further details
ParameterOn‑Device AITestify
PriceFreeFree
Rating4.4 (162 ratings)5.0 (1 ratings) — better
Positive reviews63.6% of reviews—
Number of ratings162 — better1
Update frequencyEvery 2 weeks—
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPad, Mac, Vision Pro — betteriPhone, iPad
Requires iOS18.0 — better26.0
Further details — not scored
Size1.8 GB4 MB
Age rating17+4+
DeveloperZijie DengRowena Ricalde

Customer experience

On‑Device AI

All ratings162 ratings
Positive82.1%
Neutral8.0%
Negative9.9%
Written reviews107 reviews
Positive63.6%
Neutral15.9%
Negative20.6%

Testify

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

On‑Device AI

Reported bugs

3 issues
  • Crashes on startup
  • Model selection issues
  • Inability to copy generated text

Requested features

9 requests
  • Automated multi-character conversations
  • Character set saving and syncing
  • Streamlined search integration
  • UI optimization for icons
  • Remote endpoint support for multi-agents
Show 4 more
  • HomeKit integration
  • Improved documentation
  • Enlarged agent input window
  • Per-agent model assignment

Testify

Not enough reviews yet to summarise bugs or requests.

In-app purchases

4 purchases

On‑Device AI

Subscriptions2
  • Pro Member Subscription$3.991 Month
  • Pro Member Subscription$34.991 Year
One-time2
  • Lifetime Pro Member$49.99
  • Lifetime Pro Member$99.99
1 purchases

Testify

Subscriptions1
  • Unlock all features$1.991 Month

Questions

Is On‑Device AI free?
On‑Device AI is free to download, with in-app purchases available.
Is Testify free?
Testify is free to download, with in-app purchases available.
Which has better reviews, On‑Device AI or Testify?
Testify is rated higher. On‑Device AI averages 4.4 out of 5 from 162 ratings, while Testify averages 5.0 from 1 ratings.
Do On‑Device AI or Testify have ads?
Neither On‑Device AI nor Testify shows ads.

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