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Send to Things - Add tasks to Things from your Android device
Thrive - Thrive is an intuitive tool to manage your business using the latest trends in Project Management, Dashboards, Customer Relationship Management & Accounting
NOW UI kit by InVision - A beautiful cross-platform UI kit (PSD & Sketch)
Simply.Digital - Goals & Tasks - Todo list to track your time & help set meaningful deadlines
Elements for Sketch - High-quality UI Kits in Sketch, for free