Comparison

OnStem vs STEM

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

Head to head
About

OnStem

Features
Read full description

OnStem: AI Music Separation is an on-device AI-powered music separation tool that allows you to split audio tracks into individual stems with privacy and performance in mind. Powered by optimized local inference based on the open-source Spleeter project, OnStem performs all audio processing entirely on your device, without uploading files to any server. Key Features AI Music Separation Separate audio into 2 stems: Vocal and Accompaniment Separate audio into 5 stems: Vocal, Piano, Drums, Bass, and Accompaniment On-Device AI Processing All processing runs locally using on-device AI models No audio files are uploaded or shared Your content stays private on your device Optimized for Long Audio Custom optimizations allow processing of very long audio files Designed for stability and efficiency on mobile devices Multiple Export Formats Export separated tracks as MP3, WAV, M4A, or AAC Easily integrate with other audio tools and workflows Privacy First OnStem is a local-first application. All selected files are processed on your device only. No audio data or personal information is collected, stored, or uploaded. Subscriptions and Purchases OnStem offers both subscription plans and a one-time purchase option. Monthly subscription Quarterly subscription Annual subscription One-time lifetime purchase (where available) Payment will be charged to your Apple ID account at confirmation of purchase. Subscriptions automatically renew unless auto-renew is turned off at least 24 hours before the end of the current period. You can manage or cancel your subscription at any time in your Apple ID account settings. Prices may vary by region and are displayed before purchase. Legal Privacy Policy https://github.com/yangliu-1995/stemify-legal/blob/main/Privacy-Policy/EN.md Terms of Use https://github.com/yangliu-1995/stemify-legal/blob/main/Term-of-Use/EN.md OnStem is designed for creators who value privacy, performance, and on-device AI processing.

About

STEM

Features
Read full description

FUSE VOID STEM-X is the ultimate professional AI audio separation tool, built for producers, DJs, vocalists, and cover artists who demand perfection. Powered by advanced dual-AI hybrid engines, STEM-X extracts studio-quality stems directly on your device. Whether you need a pristine vocal acapella for a remix, a high-fidelity instrumental for karaoke, or an isolated drum groove, STEM-X delivers with industry-leading speed. FEATURES: β€’ State-of-the-Art AI Engines: Choose between Vocal Priority (2-Stem) or Full Band Extraction (5-Stem). β€’ Studio In Your Pocket: Process your audio files securely with lightning speed. β€’ Pro Audio Export: Extract and export uncompressed, high-fidelity stems to your DAW or files. β€’ Fair Quota System: Only pay for the seconds you extract. No wasted credits on full songs when you only need a loop! β€’ Minimalist Studio Interface: Designed with a dark, premium aesthetic that feels like high-end studio hardware. Unleash your creativity, practice your covers, and remix the world with FUSE VOID STEM-X. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

OnStem3 screens
STEM3 screens

Verdict

The call

The clearest difference is ads: STEM at none against OnStem's shown. STEM also leads on update cadence (every 3 days vs every 3 weeks) and iOS requirement (16.4 vs 18.0). On price, in-app purchases and device support there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. OnStem sells 4 in-app purchases, starting at $0.99 per month and STEM sells 5 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

OnStem ships an update every 3 weeks, STEM every 3 days. Both last shipped on October 12, 2026.

Scorecard3 real differences Β· 3 level
OnStem versus STEM: the parameters behind the verdict, then further details
ParameterOnStemSTEM
PriceFreeFree
Update frequencyEvery 3 weeksEvery 3 days β€” better
AdsYesNo β€” better
In-app purchasesYesYes
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.016.4 β€” better
Further details β€” not scored
Size137 MB3 MB
Age rating4+4+
Developer阳 刘CEM OZAN DUZENCI

In-app purchases

4 purchases

OnStem

Subscriptions3
  • OnStem Pro – Monthly$0.991 Month
  • OnStem Pro – Quarterly$2.393 Months
  • OnStem Pro – Annual7 Days trial$8.991 Year
One-time1
  • OnStem Pro – Lifetime$9.99
5 purchases

STEM

Subscriptions4
  • Basic Plan$9.991 Month
  • Pro Plan$19.991 Month
  • Basic Plan$99.991 Year
Show 1 more
  • Pro Plan$199.991 Year
One-time1
  • Energy Token$4.99

Questions

Is OnStem free?
OnStem is free to download, with in-app purchases available.
Is STEM free?
STEM is free to download, with in-app purchases available.
Do OnStem or STEM have ads?
OnStem shows ads; STEM does not.
Which is updated more often, OnStem or STEM?
OnStem ships an update every 3 weeks, and STEM every 3 days. Most recently, OnStem was updated on October 12, 2026 and STEM on October 12, 2026.

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