Simply adding a question on the webpage of Tricider, the teacher can then share the link to the students. Students can access the link via their mobile devices such as smartphones, tablet computers and laptops, to add their ideas to the question (everyone can see their answers). Moreover, images can be embedded into it! Apart from providing their own opinions, students can vote for or comment on others' arguments, which allows them to interact with each other (of course teachers can also participate in it). In a nutshell, it's a great platform to collect all the ideas effectively and efficiently.
In terms of ELT, it is a useful tool to assist in teaching writing. Many students are afraid of writing because they are not good at developing ideas or even have no idea at all towards the given topic. In this situation, brainstorming ideas or having discussion with other students can be very helpful. These processes can be easily carried out in Tricider inside or outside the classroom as long as the participants have a device with network connection. That means, teachers can use Tricider to carry out the pre-writing task, stimulating students imagination and preparing them for the writing stage.
Obviously, in this situation, the target learners should be first equipped with computer literacy in order to use this tool. In other words, Tricider is more suitable for higher-level or older learners. Except the limitation of the target learner groups, the only drawback that I can think of with regard to this tool is the access of Internet. That said, this tool is still powerful because nowadays the need for having a connection to the internet does not constitute any barrier in many teaching context.
