I believe we should use good softwares and it should be paid. Here are a list of services I think it is good and building by a small team (< 100 people).

• Basecamp—Project Management
• Buildkite—Continuous Integrations
• Discourse—Discussion software
• Fastmail—Email
• Fathom—Analytics
• HEY—Email
• Honeybadger—Error Tracking
• Halide—Camera app on iOS