Teachers across the country are criticizing Verizon for introducing a new fee that will disrupt a popular app used to communicate with students and parents.

Remind is a kind of chat app/social media hybrid used by teachers, parents, and students to keep up-to-date on assignments and events. It also has an app-to-phone texting function that allows educators and admin to send text messages to parents and students who don’t have the app. But Verizon is introducing a new fee on app-to-phone messages—an effort to curb robotexting—that will make it too expensive for Remind to continue offering this service for Verizon phones, the company’s CEO told Motherboard.

Examples of screenshots from Remind. Image: Remind

Educators have been tweeting under the hashtag #ReversetheFee, calling out Verizon for what they see as an unfair and misplaced fee. Amanda Rich, a high school geography teacher in Texas, told me via email that she’s been using Remind for six years to communicate with students, including sending nearly 800 text messages.

“They were reminders for homework. They were reminders to study for a test. They had attachments of articles to read,” Rich said. “Each text had a purpose of helping a student.”

Remind offers two kinds of services: free access and a school or school board-wide subscription service. The subscription service users will still have all their text sent even with the increased fee, but the free users will no longer be able to do app-to-phone texting for students or teachers that have a Verizon phone account.

“We had been paying for these text messages, even under our free service, for years,” Brian Grey, the CEO of Remind, said in the phone call. “This [fee] is going to literally take what we pay for the free users from a few hundred thousand dollars a year to several million dollars a year. There’s just no way that we, as a startup company in the education space, can even come close to being able to afford that.”

The fee is not being charged to students or teachers directly, Richard Young, a director of corporate communications at Verizon, said via email. Verizon is charging the fee on app-to-phone long code SMS messages sent through companies like Twilio, which is how Remind sends its texts. Typically, mass spam texts are sent using short code (using only a 5 or 6 digit number) because they can send a bunch of messages at once. Long codes (your full, 9 or 10-digit number) are used for person-to-person texts, since they are sent individually, and at a slower rate. With companies like Twilio, a text can be sent using long code from an app to a mobile phone number, which Verizon posits can be used for spam.

“The small fee helps pay for, among other things, the work required to contain spam and fraud associated with this service,” Young said. “Remind alone sends 1.6 billion text messages a year on the Verizon wireless network through Twilio, and Twilio sends more than 4.5 billion each year. This fee will help to offset some of those costs.”

Twilio and Remind already paid Verizon the standard text messaging rate for these messages, the new fee is in addition to those rates.

Rich told me that the alternatives—sending notes through the app, or sending an email—were simply not as effective as the texts.

“Students are less likely to use the app (they don't want to use up phone storage and can't download apps over our school wifi) and email is not something that reaches students in the same way as a text,” Rich said.

Not only are students more likely to actually look at a text, but Grey told me many of their users have no other option. Many students and parents either don’t have a smartphone, don’t have a data plan, don’t have internet at home—or some combination of all three, Grey said. A text message is the most reliable and egalitarian way of making sure all students get their information they need.