Link to install Checklist for Salesforce in your organization:

Version 1.11

For the install in a Sandbox, replace the "login" in the URL above with "test".

Release Notes:

v1.11EnhancementsQuick Complete/UnComplete Tasks; Track Task Complete Date and By; Open Task query options
v1.10EnhancementsOpen Tasks performance
v1.9EnhancementsOpen Tasks volume fix; Checklist Task Report
v1.8New FeaturesChecklist for Leads; UI enhancements
v1.7New FeaturesChecklist Sequence Editor, Day Offset using business days, Clone Checklist with items
v1.6Bug fixEnsure CRUD and FLS when called via Apex directly
v1.5New FeatureChecklist Item Sequencing - Prerequisite/Dependent