Based on our record, Front seems to be a lot more popular than Followup.cc. While we know about 18 links to Front, we've tracked only 1 mention of Followup.cc. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
I'll update this if I find more. For now, this seems to be a partial solution. It's a Gmail add on (except I don't use Gmail) that adds reminders. The options when setting reminders include cancelling it if someone replies, and to remind everyone in the thread. If you combine those two, it seems like — if you use Gmail's web client and have $23/month you're dying to get rid of — a decent way to add the feature. Source: over 1 year ago
I considered trying to use one of the integration user licenses ($10 a month) or maybe something else? These emails are coming from the "Front" email service (front.com). Source: 5 months ago
Google image search say it's this: https://front.com/. Source: 11 months ago
I also googled "Shift alternatives" and found front.com which has a web application. Source: about 1 year ago
I agree with others in this thread that app-based is probably the way to go - especially if you're just building for one person. Just be sure she enables push notifications with the same settings as SMS. Others have mentioned Frontline (FYI: this product is end-of-sale), Crisp, and SpokePhone. I would also add Front as a potential app to check out as they have similar functionality. Source: about 1 year ago
For the inbox with messages, email, sms and web chat, I think Front may be what you're looking for. Source: about 1 year ago
FollowUpThen - The simplest way to schedule an email reminder
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