The EyeEm page seems to be strictly for phone photography. At least, they want you do download a phone app to get started and I don’t see any way of uploading photos from a computer. That suggests you may be using a phone for photography. If you are serious about photography, you might like to get a device that was designed as a camera instead of as a phone with a camera built in as an afterthought. Generally, cameras are easier to hold and are better at more kinds of photography. But, if you are into phone photography, you might like this link.
You may also like this:
As far as the web page goes, the TOS says they can use your photos for their advertising. It also says:
8.1 User shall indemnify EyeEm, its representatives, employees and agents and keep them indemnified against any losses, damages, expenses, costs, actions, claims, suits, litigation, causes of action, demands and liabilities which may be made against EyeEm by any third party for anything done or omitted in connection with (i) the User’s Community conduct and Content, (ii) any breach or violation of the User’s warranties or responsibility as set out in section 7, and (iii) the exercise or purported exercise of EyeEm’s rights hereunder.
8.2 This indemnification shall not cover claims by any third party which may occur because EyeEm has failed to delete or block Content without undue delay upon receipt of positive knowledge that such Content infringes the rights of any third party.
8.3 In cases of an aforementioned enforcement of claims by any third party, User will provide EyeEm with all available information that is needed for the examination of the claim and for the defence against it. User will provide such information immediately, truthfully and completely
So, this probably won’t be a problem if you are just posting trees and spiders. It could become a problem if you start posting photos of people since they could potentially use one of your photos of a person, then make you pay damages if they are sued for using that person’s image in their ad.