# TheLeft-SleepPositionalTrainer > Trains Apple Watch users to sleep on their left side to reduce heartburn. (iPhone/iPad app by Side Sleep Technologies BV.) - Source: https://appshunter.io/ios/app/theleft-sleeppositionaltrainer/id6443869099 (this page in markdown: same URL + `.md`) - Developer: [Side Sleep Technologies BV](https://appshunter.io/developer/1494478629) - Category: Health & Fitness, Medical - Price: Free - Rating: 4.00/5 from 1 App Store ratings - Age rating: 17+ - Requires: iOS 15.0 · 16 MB - Languages: English - Released: 2023-02-22 - Data updated: 2026-06-10 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/theleft-sleeppositionaltrainer/id6443869099/reviews.md ## What is TheLeft? FOR APPLE WATCH USERS Engineered to fight nighttime heartburn symptoms by training you to sleep predominantly on your left side. When sleeping on your right side, stomach acid flows into the esophagus, causing a painful burning sensation. The Left subtly trains you to sleep on your left side, where the stomach is positioned below the esophagus. The results: acid will have a harder time moving upward, meaning no more nighttime heartburn symptoms and the pain goes away. HOW DOES THE LEFT WORK? The left tracks your sleeping body position on your watch and without waking you up, provides you with a gentle vibration once it detects that you are sleeping on the right side. The vibration stimulates you to sleep on your left side more often and longer throughout the night. Your body will be conditioned not to sleep on your right side within a week. INTERESTED IN TRYING OUT THE LEFT? Natural Solution Scientifically Proven Technology Painless Sleeping Safe, Pre-Tested Non-Invasive IMPORTANT! Ensure that your iPhone and your Apple Watch are updated with the latest software version. Medical Information Disclaimer Before using this app please get advice from a professional healthcare provider or doctor. The information about health provided by the app is not intended to diagnose, treat, cure, or prevent disease. Products, services, information, and other content provided by the app, including information linking to third-party websites are provided for informational purposes only. The information offered by the app is not comprehensive and does not cover all diseases, ailments, physical conditions, or their treatment. Individuals are different and may react differently to different products. Comments made on the app by employees or other users are strictly their personal views made in their capacity and are not claims made by the Company nor do they represent the position or view of the Company. The Company is not liable for any information provided by the app about recommendations regarding supplements for any health purposes. The Company makes no guarantee or warranty to any advice or functionality offered by the app. The Company is not responsible for any damages for information or services provided even if the Company has been advised of the possibility of damages. Links to relevant papers: Certain Sleep Positions can have an effect on the % of stomach acid in the esophagus and sleeping on the left lateral position using sleep positional therapy can be advised by doctors based upon the below scientific publications. Schuitenmaker, 2022 https://www.cghjournal.org/article/S1542-3565(22)00247-6/fulltext Schuitenmaker, 2021 https://journals.lww.com/ajg/Citation/2022/02000/Associations_Between_Sleep_Position_and_Nocturnal.28.aspx Khoury 1999 https://pubmed.ncbi.nlm.nih.gov/10445529/ Opinion Paper 2020 https://pubmed.ncbi.nlm.nih.gov/34602892/ (lifestyle section) https://researchinformation.amsterdamumc.org/en/publications/esnmanms-consensus-paper-diagnosis-and-management-of-refractory-g (page 13, statement 29) Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ## Key features - Left-side sleeping training - Gentle vibration alerts - Tracks sleep position - Reduces nighttime heartburn - Non-invasive solution - Scientifically proven technology ## Frequently asked questions about TheLeft ### How does TheLeft-SleepPositionalTrainer work? TheLeft-SleepPositionalTrainer tracks your sleep position using your Apple Watch. If it detects you are sleeping on your right side, it provides a gentle vibration to encourage you to shift to your left side, where stomach acid is less likely to flow into the esophagus. ### Is TheLeft-SleepPositionalTrainer effective for heartburn? The app is engineered to fight nighttime heartburn symptoms by training you to sleep predominantly on your left side. This position helps keep stomach acid below the esophagus, reducing the burning sensation. Scientific publications are linked within the app's description to support this approach. ### What devices are compatible with TheLeft-SleepPositionalTrainer? TheLeft-SleepPositionalTrainer is designed for Apple Watch users and requires a compatible iPhone and iPod. Ensure your devices are updated with the latest software versions for optimal performance. ### Is TheLeft-SleepPositionalTrainer safe to use? The app is described as safe, pre-tested, and non-invasive. However, it is important to consult with a professional healthcare provider or doctor before using this app, as the information provided is for informational purposes only and not a substitute for medical advice. ### How often is TheLeft-SleepPositionalTrainer updated? The latest version of TheLeft-SleepPositionalTrainer is 1.0.4, and it was last updated on April 16, 2025. This indicates recent development and support for the application. ### What is the user rating for TheLeft-SleepPositionalTrainer? The app has a rating of 4.0 stars based on one review. This suggests a generally positive user experience, though more reviews would provide a broader perspective. ### Does TheLeft-SleepPositionalTrainer have ads? No, TheLeft-SleepPositionalTrainer does not contain advertisements. It is a free application designed to provide a seamless user experience without interruptions. ### What is the age rating for TheLeft-SleepPositionalTrainer? The age rating for TheLeft-SleepPositionalTrainer is 17+. This is likely due to the nature of health-related content and the need for users to understand the medical disclaimer. ## Version history (last 4 releases) ### 1.0.4 — 2025-04-16 FaQ content was updated. Compatibility with newer OS version was tested. ### 1.0.3 — 2023-03-24 Compatibility enhancements with newer WatchOS versions ### 1.0.2 — 2023-03-02 Product label was updated. ### 1.0.1 — 2023-02-22 No release notes. ## More apps by Side Sleep Technologies BV - [LEFT Sleep Position Trainer](https://appshunter.io/ios/app/left-sleep-position-trainer/id1490471203) - [SNOOOR Sleep Position Device](https://appshunter.io/ios/app/snooor-sleep-position-device/id1521001705) All apps by Side Sleep Technologies BV: https://appshunter.io/developer/1494478629 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*