Ten points! What is it meant by 'viral effect' here in this context?

[Brent]

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Hello! Head's up: your gallery has just received another submission. You can help create a viral effect by frequently checking your app and interacting with your audience, and by promoting your gallery by emailing your customers or by advertising it on Facebook or other websites

[Rob]

What it is saying that the more you look at your app and you interface...the more hits you have ...the more people get to know the more people want to know....think of it like the flu...the more people you see the more it will spread etc. So what it is saying is the more exposure you have the word will spread...
Hope this helps