Telegram
The chatbot Skeddy can help to create Telegram messenger reminder bot and lets you create a calendar reminder. Search "skeddybot" in Telegram, after start the chat to manage reminders.
Skeddy is a simple yet powerful reminder tool that can help you create and manage your reminders. https://skeddy.me/
Vkontakte
What can do this bot?With Skeddy you can create and manage your reminders, which then are sent to you via Telegram.
You can create simple reminders using natural language, just sending messages like: "call John in 20 minutes", "check your email tomorrow at 10am" etc.
Or, using bot Web-interface, you can create reminders with complex schedule, like "pay bills on the 1st day of every month at 7pm" etc.
So, if you need some simple yet powerful reminder tool, you should definitely try Skeddy.
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Skeddy