World Politics Review published on 11 January 2017 an article titled "As ISIS Struggles for Influence in Somalia, al-Shabab Remains the Main Threat" by Joshua Meservey.
The author concludes that while there are small numbers of ISIS sympathizers in Somalia, they are preoccupied with dodging al-Shabaab death squads. Winning many Somalis' acquiescence or loyalty is beyond the Islamic State's capacity at the moment.