The best alternatives to Franke are Missive, MailClark, and Alert.email. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Franke?
Postman Recorder by DevTools— Export Postman APIs from browser
Gmelius is the first collaboration platform designed for G Suite and your company's daily apps. Gmelius transforms Gmail into your team's workspace. Collaborate in real-time thanks to shared mailboxes, a help desk, Trello-like boards and sales automation tools.
SharedBox gives you a unique email that connects to your Slack account. Emails sent or forwarded to it is sent to your choice Slack channel, properly threaded. Collaborate with your team, comment, add notes and reply directly from Slack.