The link takes you to a zip file on dropbox that allows you to download about 200 MBs of wireframing and Mockup kits

https://www.dropbox.com/s/703vwyqvrsgeygn/Wireframing-UI%20Kits.zip?dl=0

Apple Design Site

https://developer.apple.com/design/

Apple Human Interface Guidelines

Get in-depth information and UI resources for designing great apps that integrate seamlessly with Apple platforms.

https://developer.apple.com/ios/human-interface-guidelines/overview/themes/

Google Material Design

Material Design is a unified system that combines theory, resources, and tools for crafting digital experiences.

https://material.io/

Material Design Guidelines

We challenged ourselves to create a visual language for our users that synthesizes the classic principles of good design with the innovation and possibility of technology and science. This is material design. This spec is a living document that will be updated as we continue to develop the tenets and specifics of material design.

https://material.io/guidelines/

Everything you need to know about conducting useful user interviews

Creating products based on your own needs is easy – if you’re building something just for yourself, you don’t need to talk to anyone else because you know what you want.

It’s pretty unlikely that you’ll ever design a product for yourself. If you want to make a product that will be used by other people, it’s essential to talk to them to discover their wants, needs and, experiences.

The Art of the User Interview

Presentation 05 – UI:The Principles of Design

https://docs.google.com/presentation/d/1q8BUDXREMLli5V4zgNb3dnWKEyc1KMwiRHUJlPZ0MPY/edit?usp=sharing

Presentation 06 – Understanding UI Design

https://docs.google.com/presentation/d/1bQXo0yif3NeYYAagTFas-coVDTV2S4Qf-JQdCC3W-tQ/edit?usp=sharing

Presentation 07 – Understanding Wireframes

https://docs.google.com/presentation/d/1PBo_b2ywVDulSrvSfm4n9yKnkI9YFcHhLLY5k4jfoyA/edit?usp=sharing