Instagram's mobile website now supports photo uploads if you're on the go and aren't feeling like opening the application to complete the process. Granted, if you're on a mobile device and you use Instagram, chances are you have the app and are more likely to be using this for all your Instagram pics, but that doesn't mean that users wont run into situations where it would be more convenient to just upload a picture from the mobile version of the website instead, and there are those who may have phones with smaller amounts of internal storage where it might be easier to upload from a mobile browser as opposed to downloading the Instagram app and taking up space on their device.
Whatever the case may be, the option to go to Instagram's website from mobile versions of Chrome, Firefox, or other browsers is now available for those users that may either need it or want it. It's simple enough to use the upload feature from the mobile version of the service too as the upload button resides in the same exact spot as in the application, so there won't be any confusion from users who upload pics from within Instagram as opposed to sharing the photos with Instagram from the gallery. That being said, the upload feature does use a different icon in the app, which is represented by a "+" icon, whereas the mobile website has a camera icon.
Instagram has been making quite a few changes lately in order to improve the service for its users with features like an offline mode which is now currently in testing via the Android version, and they even recently added a new Collections feature that is similar to Pinterest. These new features and improvements seem to be working for Instagram as it now has more than 700 million users in total as of the end of April, which is up from 600 million in December of 2016 according to Instagram. Whether you choose to interact with Instagram through the mobile browser or through the app, you shouldn't have any trouble uploading your best pics to share with the world.