Mockups are a great alternatives way to enhance your design work, it will be help to make your design process much easier and also help to enhance your portfolio either for web or graphic design.

1. Pixeden is the best place to find premium and free psd mock-up templates, it provide quality free web resources and graphic design templates.
2. Smartmockups is one of the best online mockup generator you can find online, and a fantastic desktop app that gives you the power, speed, and resources you need to create stunning photorealistic mockup designs. And with an affordable Premium subscription, you can use both web service and desktop app for Mac and Windows, to get entirely creative and have your smart mockups ready for use anytime anywhere. Simplicity, flexibility, and speed at its finest!
3. As a collaboration platform for team, Futuramo has a loads of visually compatible icon set on the web. In specific, it offers 45,000 UI icons (with 3,000 icons in 16 styles) that are ready to mix and group together in dedicated sets. All of the icons are impressive and crafted with utmost precision so as to meet the most demanding design requirements.
4. Pixel Buddha offers fresh mockups for creative community. They offers icons set and best free mockups PSD for free. You can use them for your personal and commercial project. There are wide range of mockup PSD in this website.
5. Use FreePik for free mockups, however if you are not paying for a subscription, attribution may be required.
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