We have a sample of say 1000 individuals randomly sampled from a country that we will interview. The names of these individuals are uploaded in the ODK app. For each individual, we know the names of shops in their neighborhood (this can also be uploaded in the ODK app).
We want to collect information on the shopping experience of the individuals in all the shops in their neighborhood. The first question would simply be: have you ever shopped in name of the shop and will also show a picture of the shop. Answer options would be yes/no and if no we proceed to the next shop in the neighborhood and if yes we ask a range of questions (eg. did you like the music that was playing in the shop,...). After all questions are answered we go to the second shop, etc until all shops in the neighborhood are exhausted.
Note that some individuals will have only one or two shops in their neighborhood, others may have up to 20 shops.