Stuart Hall's reception theory is the idea that communication is a process involving encoding by producers and decoding by audiences. There are three hypothetical positions from which messages meanings may be decoded and I will go through each one and how it applies to Zoella.
The dominant also known as the hegemonic reading is the position that the encoder will want the audience to take as it is the encoder's intended meaning. Zoella attempts to represent herself as the 'girl next door' sort of character and just an ordinary young girl who has a love for all thing fashion, makeup and food. This can be seen in multiple ways such as her the set of her videos, her 'bedroom' which features fairy lights which could be considered similar to the bedroom of the typical 12-24 year old girl which is the main chunk of her audience, so she comes across as relatable. This is despite even the room itself being part of the media construction and just being a room she uses for videos. She maintains gender roles and doesn't attempt in anyway to go away from this with her content barely changing over the last 7 years and tries to stay away from controversy and preserve a squeaky clean image. Her audience who watch her videos week in, week out will take the dominant position and hegemonic reading with them seeing her as the sort of 'character' that she tries to show herself as just a normal girl interested in typically girly things and who wants to share these things with her audience.
Some people may take a negotiated position, this is when the legitimacy of the encoder's message is adapted or negotiated to better fit the decoder's own individual experiences or context. Some people may take the negotiated reading in a number of ways. You could also apply David Gauntlet's Pick N Mix theory as the audience may use her content such as makeup and fashion to benefit them but may see through the 'character' of Zoella and see it as an act put on to gain viewers and that it isn't completely real and they may only use certain parts of her channel or blog such as tutorials but may not enjoy or like the 'Zoella' character. Furthermore, for some people it maybe the other way around with them not particularly caring about the content featured in the videos and blog posts but consume the content mainly for Zoella herself. This is the position that in the modern day age of social media, the majority of us may take with us being more media savvy than ever and will be able to take multiple different viewpoints.
However, there may be people who will take the oppositional reading, where the encoder's message is understood, but the decoder disagrees with it, reading in a contrary or oppositional way. With Zoella, people may be able to see through her and that despite 27 years old she still acts like a young teenager and that it is very much an act to appeal to her younger audience. Also, some may see her as a bad role model and negative influence on young girls and women due to her very much conforming to gender roles and not exactly inspiring them to reach for there dreams but to conform to society instead. Furthermore, Zoella has been at the heart of many controversies such as bigoted tweets from the past and also her £50 advent calendar an this could make people take an oppositional reading towards her.