1. Data Sources: Context.IO can access email data from multiple email providers such as Gmail, Yahoo, and Outlook, while mailparser.io focuses solely on parsing and extracting data from emails.

2. Scope of Use: Context.IO is more suited for developers who require access to raw email data and metadata, enabling them to build custom email applications, whereas mailparser.io is designed for users who primarily need data extraction and parsing services without direct access to raw email content.

3. API Integration: Context.IO offers detailed and flexible API documentation for developers to integrate email data into their applications, while mailparser.io provides a simplified API suitable for easier data extraction and automation processes.

4. Data Manipulation: Context.IO allows for a wider range of data manipulation and interaction with email data, including the ability to search, filter, and download email attachments, whereas mailparser.io focuses on efficiently parsing emails and extracting specific data fields.

5. Customization Options: Context.IO provides more customization and configuration options for developers to tailor their email applications to specific requirements, whereas mailparser.io offers predefined parsing rules and templates for quicker data extraction without extensive customization abilities.

6. Scalability and Pricing: Context.IO offers different pricing tiers based on usage and scalability needs, suitable for larger projects and applications, while mailparser.io provides a simpler pricing structure more focused on the amount of data processed, generally preferred for smaller-scale data extraction tasks.

In Summary, Context.IO provides developers with access to a wider range of email data manipulation and customization options, while mailparser.io focuses on efficient data extraction and parsing services for users with simpler needs.