I have been using UniSender for email newsletters for about two years. It is one of the best Russian services for email marketing. Pros: a convenient editor with templates, automation of mailing chains, statistics on opens and clicks, A/B testing. The free plan allows up to 1500 emails per month. High email deliverability and a good reputation for the service. Customer support is responsive. As for the cons: the prices for paid plans may seem high for small businesses with large databases, but overall the service is excellent. I recommend it.
