SurveyMonkey is the world's leading online survey platform, but it is complicated and expensive.
Autopilot has the ability to create "Capture forms" which can act as surveys. You can then send those responses to yourself via Slack, SMS, and analyse the responses in ledger form, reports, and advanced graphs.
Autopilot also allows you to have automated survey follow ups and segment your customers into audiences based on their survey response.
Mixpanel is the most advanced analytics platform for mobile & web. Autopilot has graphing and analysis capabilities rivalling Mixpanel, and additionally allows you to segment your customer base and send email, SMS and in-app messaging campaigns to those segmented customers.