Free App to create advertisement....

 There are several free apps and online tools that you can use to create advertisements effectively. Here are some popular ones: 

1. Canva: Canva is a user-friendly graphic design platform that offers a wide range of templates for social media ads, flyers, posters, and more. It has a drag-and-drop interface and a variety of design elements. 

2. Adobe Express (formerly Adobe Spark): Adobe Express provides tools to create social media graphics, web pages, and short videos. It offers templates and a simple interface, making it easy for beginners. 

3. Crello (now VistaCreate): Similar to Canva, VistaCreate offers numerous templates for ads, social media posts, and more. You can customize graphics with images, text, and animations. 

4. Design Wizard: This tool allows you to create images and videos for your advertising needs. It has a wide range of templates and customization options. 

5. Piktochart: While mainly used for infographics, Piktochart can also be used to create visually appealing advertisements. It offers templates for posters and presentations as well. 

6. PosterMyWall: This platform allows users to create promotional graphics and videos quickly. You can choose templates suitable for various advertising platforms. 

7. Snappa: Snappa provides access to numerous templates and stock photos, allowing you to create ads for social media, blogs, and print. 

8. Visme: This tool helps with creating visual content, including advertisements, infographics, and presentations. It has free templates and customizable design options. 

While most of these tools offer free versions, some features or assets may be premium or require a subscription. Always check the licensing for images and design elements if you're planning to use them commercially.