One popular option is PouncerAI, which offers a sophisticated RSS Reader to quickly find relevant jobs and AI-based proposal templates to craft your own cover letters. It's got a one-tab interface, real-time job alerts and a built-in Job Inbox to keep things organized. It's secure and Upwork Terms of Service compliant, and you can try it for free for 14 days and pay for subscriptions.
Another is JobFlux, an automation tool that uses AI to help you find jobs. You can set up your job preferences and work experience, and it'll create custom cover letters for each job it finds. JobFlux also offers a smart job tracker, premium subscription service and notifications to keep you up to date on new jobs.
If you prefer something more flexible and customizable, UpScout offers unlimited searches and filters with email alerts when new jobs match your criteria. The free version offers daily job emails and unlimited searches, but the Pro version adds hourly job updates and future AI proposals, Slack notifications and WhatsApp alerts. It's designed to save you time and cut down on the drudgery of finding good Upwork jobs.