In Tandem you can do simple editing tasks using two resizable, independently scrollable editing areas
Tandem also remembers where you left it last, so you can come back to it later - But doesn't currently save what you're doing anywhere other than on your device.
- Translating documents - paste the text you want to translate into one area, and start your translation in the other.
- Responding to email - paste the email(s) you're responding to in one area, and compose your email in the other.
- Composing email - use one area for holding notes or points you want to make, which you can refer to whilst composing in the other.
Why two editing areas?
Email example: Usually an email is sent in response to something, even multiple things, and often you have to go back and forth between writing the email and referring to previous email(s), which is a time consuming task and difficult to balance. So, by simply pasting your reference emails in one area, and composing in the other, you can now simply scroll up and and edit down these areas (independently), making sure you've answered all of the relevant items.
Originally, the idea came about because email clients - both web (GMail, Hotmail, etc) and desktop (Apple Mail, Outlook, etc) - either provide less space to compose your email or make it difficult for you to refer to the email(s) you may be responding to whilst composing.
Tandem is simple intentionally; it aims to provide a large space for you to just compose an email, and another space for you to put everything you need to refer to whilst composing that email - two activities that are not as easily done in today's email clients.