Reply.io

Reply.io is the sales engagement and automation platform Oleg Bilozor bootstrapped from Kyiv, Ukraine in 2014. It grew to $10M+ ARR with 200+ employees serving 3,000+ sales teams by offering the most complete outbound automation in the mid-market: email sequences, LinkedIn automation, phone calls (with a built-in dialer), SMS, and WhatsApp — all orchestrated from one platform, with AI writing suggested sequences based on the prospect's profile. Reply.io's data platform (a B2B contact database of 140M+ contacts that users can search and import directly into sequences without leaving Reply) transformed it from a sending tool into a full prospecting-to-outreach stack. The AI sequence generator (input a target persona description and ICP, get a complete multi-step sequence with draft emails tailored to that audience) became the product's most viral feature — salespeople shared the generated sequences publicly on LinkedIn, generating massive awareness.