Building focused, private productivity tools for Gmail™
We build focused, private productivity tools for Gmail™ and Google Workspace™ — designed for professionals who need control, reliability, and privacy.
To provide tools that respect your privacy while supercharging your workflow. AutoSend was built to solve the deliverability issues caused by sending too many emails too quickly.
Every great product is born out of frustration. For us, that frustration was the state of email automation. We noticed that professionals were forced to choose between two bad options: either use complex, expensive third-party platforms that compromise privacy, or send emails manually, wasting hours of valuable time.
We asked ourselves: Why can't there be a simple tool that just works inside Gmail™? Why do we need to export our contacts to another platform? Why do so many mass emails end up in spam?
The answer to that last question was simple: Sending too fast. When you send hundreds of emails at the exact same second, email providers immediately flag your account as a bot. Your sender reputation plummets, and your important messages never reach their destination.
That's when the idea for AutoSend (now MailFlow) was born. We wanted to create a tool that sends emails the way a human would: one by one, with natural, randomized delays between each message.
We believe that software should be an extension of your natural workflow. It shouldn't require you to learn a new interface, memorize new shortcuts, or adapt your processes to fit the tool. The tool should adapt to you.
This is why we built our solution exclusively as a Google Workspace™ Add-on. By living natively inside the Gmail™ interface, we eliminate the friction of switching context. You compose your email the same way you always do. You manage your contacts the same way you always do. We just handle the delivery.
Furthermore, we believe in the principle of minimal data extraction. In an era where tech companies hoard every data point they can find, we take the opposite approach. We only process the data absolutely necessary to deliver your emails. We don't read your inbox. We don't track your browsing history. We don't sell your data to third parties.
Building a reliable batch-sending tool inside Google's infrastructure presented unique technical challenges. Google Apps Script™ has strict execution time limits. A script can only run for a maximum of 6 minutes before it is forcefully terminated.
If you are trying to send 100 emails with a 1-minute delay between each, that process takes 100 minutes. Obviously, a simple loop would fail after the 6th email.
To solve this, we engineered a sophisticated state-management system using Google Apps Script PropertiesService and Time-Driven Triggers.
When you start a batch, our system doesn't try to send everything at once. Instead, it sends the first email, calculates the exact timestamp for the next email based on your delay settings, and schedules a future trigger. The script then completely shuts down, consuming zero resources.
When the scheduled time arrives, Google's servers wake up our script. The script checks the state, sends the next email, schedules the next trigger, and shuts down again.
This architecture allows us to run indefinitely, bypassing execution limits entirely, while maintaining 100% compliance with Google's platform rules.
Because we operate within the Google Workspace™ ecosystem, we inherit Google's world-class security infrastructure. Authentication is handled entirely via OAuth 2.0. This means we never see, store, or process your Google password.
When you grant our Add-on permissions, you are authorizing a secure token that can be revoked by you at any time from your Google Account settings.
We take our commitment to the Google API Services User Data Policy very seriously. Our use of information received from Google APIs strictly adheres to the Limited Use requirements.
Our users come from diverse industries and backgrounds, but they all share a common need: reliable, scalable, and private email communication.
For early-stage startups, every email counts. Whether you are reaching out to potential investors, onboarding your first beta testers, or announcing a new feature launch, you need to ensure your message lands in the primary inbox.
Founders use our tool to send personalized updates to their stakeholders without looking like they used a mass-mailing service.
Independent professionals rely on cold outreach and network nurturing to maintain a steady pipeline of clients.
With our custom time delays, freelancers can schedule their weekly outreach in one batch on Monday morning, and let the system slowly deliver the emails throughout the day. This maintains a healthy sender reputation and increases reply rates.
Realtors need to send property alerts, open house invitations, and market updates to their client lists.
Since these emails often contain large images and attachments, sending them all at once through a standard Gmail™ account is a surefire way to trigger spam filters. Our Safe Mode pacing ensures that these heavy emails are delivered smoothly.
Teachers and administrators frequently need to communicate with parents and students. Our tool allows them to send important announcements directly from their official school email addresses, ensuring high deliverability and trust.
We are constantly iterating and improving our platform based on user feedback. While our core focus remains on simple, native batch sending, we are exploring new ways to enhance the Gmail™ experience.
Future updates will focus on deeper integration with Google Sheets™ for advanced mail merging, as well as enhanced analytics to track open rates without compromising recipient privacy.
Thank you for trusting Truellion Technologies with your email automation needs. We are honored to be a part of your daily workflow.