My DS is now 13 months with 8 teeth. He has been eating snacks since 6 months (he is a very hungry boy). He loves rice crackers with cream cheese or carrot & cumin dip or hummus, mango, banana, melon, cheese, cherry tomatoes, roast tomatoes, bagels, batons of steamed or roasted vegetables (carrots, mini sweetcorn, pumpkin, broccoli, asparagus, aubergine, courgette). I recently discovered giving him little puffed corn baby snacks (shaped like a cheerio) for him to pick up, one by one.
When I have time I make a batch of savoury muffins (with cheese and spinach, for example) and put them in the freezer. I also recently made small pumpkin patties with cheese and breadcrumbs which I keep in the freezer and cook as a snack.
At this age, I don't think it matters if it isn't what we traditionally think of as 'snack' food. Just something to tide them over until the next meal (I know my son needs this).