A new Mac app called RPLY launches today, designed to help texters achieve “inbox zero” on iMessage.
Targeting those who often forget to reply and leave their friends on delivered for days, RPLY utilizes AI to identify missed texts and suggests responses to prevent users from unintentionally ghosting. The AI assistant can automatically respond to messages in a user’s inbox that have not received a reply for over 24 hours.
RPLY is the brainchild of Molly Cantillon, a 21-year-old Stanford dropout who created NOX, a personalized AI assistant for iOS backed by OpenAI’s startup fund.
“RPLY was built to handle ‘text debt,’ mentally replying but never hitting send, getting distracted, or just forgetting. The core idea is making texting feel less like a burden while still maintaining authentic connections,” Cantillon told TechCrunch.
Although AI-powered smart reply technology has been around for nearly a decade and is used by major tech companies like Google, Cantillon noted that she has yet to see a solution like RPLY for iMessage.
RPLY’s iMessage assistant goes a step further by analyzing a user’s entire text history to craft replies that align with their writing style and personality, resulting in natural-sounding responses.
Taking inspiration from Inbox Zero, a popular virtual assistant for email, RPLY also filters out unanswered messages. It even provides users with a clear overview of unread texts, allowing them to see how many of their messages need responses. This feature offers a quick summary, making it easier than scrolling through iMessage.
Cantillon believes that the unanswered message filter is “a simple but vital feature that Apple surprisingly overlooks.”
The app also includes a statistics page that displays the average weekly response time and tracks an “inbox zero streak,” which tells users the last time they had zero unread messages. To make users more aware of their texting habits, it displays stats like “Those You Answer Quickest” and “Those You Like to Ghost.”
During our testing of the app, TechCrunch found that the AI replies sounded natural and demonstrated an understanding of context. Most of the people we messaged didn’t realize the responses were AI-generated. However, some users noticed something was off when the AI placed a comma after “haha.” It also didn’t use any emojis, and we wish it had.
RPLY has already attracted a decent amount of interest, having signed up 1,000 paid users so far. Cantillon said that many people drawn to the app are in tech, creative, and business fields. The app is also targeted to founders, recruiters, retail agents, and other professionals who are overwhelmed with crowded inboxes. College students might find the app convenient as well.
While many people are drawn to RPLY for its helpful features, it also raises the question: can relying on AI lessen the emotional connection we get from texting? This is a topic that’s come up before with the rise of generative AI tools, but it’s worth thinking about whether the ease of using AI is really worth giving up those heartfelt exchanges.
Additionally, to use the app, users must grant permission for it to access all their text messages and contacts. This requirement may raise concerns for some people, as it means that an AI would examine personal conversations with friends and family.
According to RPLY’s privacy page, the app doesn’t use text content to train generalized AI models, and the company follows a “strict zero data retention policy,” meaning data isn’t stored and gets immediately deleted after processing. Also, RPLY says it doesn’t sell user data to third parties.
Cantillon added that RPLY offers a local Llama-based option (Meta’s AI model) for users who want to keep all text data processing entirely on-device, ensuring no text data is ever uploaded.
It’s normal for AI systems to require user data to function properly, but it’s important to note that even if companies claim strong security practices, breaches still happen. Chinese AI company DeepSeek recently dealt with an exposed internal database that contained sensitive information, including chat histories. Always be aware of the privacy risks involved.
RPLY is currently only available on macOS devices. Apple is known for its strict App Store guidelines, which suggests that RPLY may have developed a Mac app as a strategic workaround.
In the future, Cantillon envisions expanding RPLY’s availability to platforms such as WhatsApp and Slack. However, it remains uncertain whether this will happen, and there may be concerns among users on Slack, an app used by employees, regarding the willingness to share extensive information with an AI company.
It’s also on the pricier side: the base subscription costs $30 per month after a 14-day free trial.
