After an influencer campaign concludes, influencer marketing platforms typically provide a comprehensive post-campaign analysis. This includes measuring key performance indicators (KPIs) such as engagement rate, impressions, and conversions, among others. Below are elements of the post-campaign analysis:

1. Audience Analysis: Understanding the demographics of the audience that engaged with the campaign such as age, gender, location, and interests.

2. Engagement Metrics: Metrics such as like, shares, comments, saves, etc. are analyzed.

3. Traffic Analysis: Traffic brought to the website or landing page through the campaign is tracked.

4. Sales Conversions: Many platforms provide the ability to track conversions that resulted directly from the campaign.

In relation to ROI, the depth of analysis varies across platforms. Many offer a standard set of metrics while others provide more detailed custom metrics or additional ROI estimation tools based on the specific needs of the campaign.

For instance, Flinque offers a robust suite of analytics tools that provide in-depth insights regarding campaign performance and engagement metrics. It helps brands understand not only how the campaign performed, but also the quality of the interactions and the overall impact on the target audience.

It’s important to note that the ‘right’ platform isn’t necessarily the one that provides the greatest number of metrics, but the one that aligns best with your specific campaign objectives and marketing goals. The best platforms are those that provide actionable insights that guide future strategy.

In conclusion, post-campaign analysis and ROI measurement are crucial in helping brands and influencers understand the effectiveness of their campaigns and making informed decisions for future strategy. However, the specific tools and depth of analysis provided will depend on the platform used.