OpenPPG vs Holiday Messenger

OpenPPG is a free, research-oriented iOS application designed to close the gap in accessible and transparent PPG data acquisition. Built by researchers for researchers, it enables recording of raw, high-quality photoplethysmography (PPG) signals directly from the smartphone camera, with full export for scientific analysis. Key Features • Raw signal access – capture unprocessed PPG waveforms with complete control over export (CSV format). • Flexible preprocessing – raw signals, basic and advanced filtering, signal quality assessment or fully calculated metrics in one app to enhance your research • Feature extraction – access directly over 11 automatically calculated temporal and morphological metrics without need for advanced signal processing • Metadata & annotations – mark events while taking measurements in real time and customise forms to fit your study protocol • Explainable pipeline – reproducible acquisition process with transparent documentation to ensure research reliability. Why OpenPPG? Most mobile tools restrict access to raw data, hide acquisition details, or require payment. OpenPPG removes these barriers by providing a free, standardised, and reproducible way to acquire PPG signals. It supports innovation in signal processing, machine learning, and digital biomarker discovery. Important: OpenPPG is intended solely for research purposes. It is not a medical device and must not be used for diagnosis, treatment, or patient self-monitoring.

Send personalized holiday greetings to everyone you care about - without group texts! HolidayMessenger lets you write your message once, choose your recipients, and send individual personal texts to each person. Each message is sent separately (not a group chat), so replies stay private!! Create templates for holidays, birthdays, and special occasions, personalize with names automatically, and send manually (free) or automate with Pro features. All your data stays on your device - privacy first, always. --- DETAILED FEATURES Message Templates • Create and save custom message templates for any occasion • Pre-loaded templates included for holidays, birthdays, and special events • Personalize with {FullName} and {FirstName} placeholders • Organize by category: Holidays, Birthdays, General, Seasonal • Edit, favorite, and manage your templates Smart Contact Selection • Native iOS contact picker with built-in search • Multiple phone number support • Create custom recipient groups and edit them anytime • Combine saved groups with ad-hoc picks • Access existing groups from your Contacts app Two Ways to Send FREE VERSION: • Compose your message and select recipients • Send manually through Apple's Messages app • Each message requires a quick tap to send • Perfect for smaller lists or one-off messages • Free messages end with a short "-Sent using HolidayMessenger" signature (removed in Pro) PRO VERSION ($1.99 one-time purchase): • Automated sending via Apple Shortcuts • Send to all recipients with one tap - no per-message interaction needed • Secure token-based system ensures your data stays private Message History • See all your sent messages in one place • View personalized messages for each recipient • Track when messages were sent • Delete individual or all history entries ***Privacy First*** • All data stored locally on your device • No cloud storage or third-party servers • Your contacts never leave your device • No tracking or analytics • Full control over your data PERFECT FOR • Holiday greetings (Christmas, New Year, Thanksgiving, etc.) • Birthday wishes • Thank you messages • Congratulations and celebrations • Staying in touch with friends and family • Sending personalized messages to groups without group chat chaos HOW IT WORKS 1. Choose a template or write a custom message 2. Select your recipients from contacts 3. Review and personalize if needed 4. Send all at once (Pro) or send manually one by one (Free) For Pro users, the HolidayMessengerPro Shortcut handles automated sending through your Messages app, making it effortless to send personalized greetings to everyone on your list. FREE TO START HolidayMessenger is free to download and use. The free version includes: • Unlimited template creation • Contact selection and management • Manual message sending • Message history • All core messaging features Upgrade to Pro for just $1.99 (one-time purchase) to unlock: • Automated sending via Shortcuts • No per-message taps required WHY HOLIDAYMESSENGER? We've all been there - the holidays roll around and you want to send warm wishes to 20, 30, or even 50 people. But sending individual texts takes forever, and nobody wants to be stuck in a group text where everyone's replies ping your phone all day long. HolidayMessenger solves this by letting you write your message once, choose who should receive it, and send it as individual, personal texts to each person. It's like you typed them out one by one, but done in minutes instead of hours. Perfect for busy people who want to stay connected without the hassle. SUPPORT Questions or need help? We're here for you: • Email: support@holidaymessenger.com • Website: holidaymessenger.com • Privacy Policy: Available in app and on our website Download HolidayMessenger today and make sending personalized messages effortless!