# Features - [Phone API Keys](https://docs.httpsms.com/features/phone-api-keys.md): Manage multiple Android phones under one httpSMS account by creating unique API keys per phone. - [Control SMS Send Rate](https://docs.httpsms.com/features/control-sms-send-rate.md): Whether you're sending hundreds or thousands of messages, our intelligent queue system ensures reliable delivery at your chosen pace. - [Scheduling SMS Messages](https://docs.httpsms.com/features/scheduling-sms-messages.md): Complete guide on scheduling SMS messages to be sent in the future on the httpSMS platform - [Outgoing Message Queue](https://docs.httpsms.com/features/outgoing-message-queue.md): Complete guide on how httpSMS queues outgoing SMS messages for reliable delivery, including rate-based dispatch, scheduled sending, and send schedule windows. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.httpsms.com/features.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.