Spam is everywhere. 70% of email traffic is spam. Email clients become smarter and smarter as they need to distinguish spam from not-spam. And they make algorithms more complex. But they start to fail. So here’s the war: spammers vs. developers of email clients and email servers.

Not only users suffer from this war, but also developers of useful services and apps. For example, you. Your emails hit spam instead of Inbox. As a result people don’t see your letters, don’t click on the links in the letters and don’t come back to your apps. Retention rate decreases, churn rate increases. That’s no good.

Sooner or later each startup will face the problem and understand that it’s better to send letters not from your own email servers, but from special services which increase delivery rate (SendGrid, Mandrill, etc.).

But you as an app author will be quiet, as you know whether your emails are in the Inbox or in the Spam/Junk folder. There’s a special service for that – IsNotSpam.

It works quite simple – you send letters from a special unique address which is assigned to you (e.g. [email protected]) and then open a delivery report.

Along with this, the service checks your email domain setup by letter headings and SMTP session: SPF record, Sender-ID, DomainKeys, DKIM. Your letter is also checked by SpamAssassin.

If you want to continue sending letters from your servers, I suggest you read this “spam checking guide” and carry out everything it tells about. It’ll really increase the delivery rate of your emails.