Photo adverts are the most vibrant and appear on multiple places throughout the app.
Yet, on each occasion they do not impede nor interrupt the end-user navigation within the app.
The first image above shows the store list where a red flag is found next to store named "Blonde Experiences" to indicate that a special consisting of multiple photos is present. The icon next to each shop indicates the category of the shop. This may be replaced with the shop's own logo if desired.
The second image shows when a store is selected (from the first image). The store details are displayed as well as one of the scrollable photos for the advertisement.
The third image shows a typical map where several stores are marked with red flags to indicate that photo specials are present for each one of them. At the top of the screen there are thumbnails for random adverts for other stores. These thumbnails are scrollable and 'clickable" to view the store deal. In the map, the icon representing the shop's category is displayed. This may be replaced with the shop's own logo if desired.
Lastly, when you "hover" above a store marked with a red flag, the specials for that particular store will appear on the top thumbnail window.
The thumbnail window on top of the map changes to a new random display every minute to give all advertisers an opportunity to display their specials.
Notice how in all these cases there is no imposition or hindrance to the user via "pop-ups", etc.
For best results, photos supplied ought to be in portrait mode, approximately square dimensions.