A critical factor that you need to consider when selecting an influencer platform is the social media platforms for which they can find influencers. Some of the bigger influencer platforms cover nearly every major social media platform. Others specialize in one or two social networks. Ultimately you need to market where your potential customers are. So, for instance, TikTok or Instagram may be best if you sell to young women, LinkedIn if you sell B2B, Twitter for the politically aware, and Facebook for older people.