推荐回答(5个)
以官方的视点来说,苹果曾在iOS安全白皮书中说到:“为了防止设备被降级至缺少最新安全更新的软件版别, iOS运用了一种名为体系软件授权的流程。假如答应降级,可以以物理形式接触到设备的进犯者将可以装置前期版别的iOS,并利用已在新版iOS中被批改的安全缺点”。
也可以了解为,苹果不答应设备降级是单方面出于安全视点的考虑,苹果的产品要是想卖给政企客户的话就要经过各种安全认证,而苹果明显不答应降级进犯的存在。

从逻辑上来说,这种解说还算行得通,其实从任何视点来讲,单纯的不答应降级都是可以被用户了解的,就好比个人电脑的Win 7直升Win 8后也无法用惯例的手法降级相同,想要用回Win 7,就要重装体系。
大部分用户无法承受的应该是iPhone手机无法刷机这一点,以这种不答应刷机的方法来提高体系的安全性,的确有些过于独裁了,究竟iPhone的用户集体有很多,是否挑选安全的运用环境应该是由用户自己来决议的,比方政企客户想要安全性,那么大可以跟着体系的更新进行晋级,而普通用户体会新版别后觉得不适应,理应可以随意刷机降级,而不是像现在这样,只要新版别推出后那一段限制的时刻才干降级。
现在有一种说法是,苹果为了推进新设备的销量,成心让旧的设备在晋级到新体系之后呈现卡顿等状况。比方iOS 11刚刚发布,一些iPhone 6甚至iPhone 7手机在晋级之后,就呈现了体系不流通、耗电太快、部分APP无法运用等问题。近期哈佛大学的一项研究报告标明:每当苹果发布新的iPhone手机之后,网络上查找“iPhone变慢”的人就会增多

别的还有一点,苹果制止降级可能也是为了防止碎片化,削减新开发使用所面临的前史包袱。
1、晋级之前注意备份材料。iOS晋级会保存原体系中的用户数据,可是降级操作会导致手机中的数据悉数清空。所以在晋级和降级之前,应该注意备份手机中的材料

iOS的备份和康复机制是:当时版别的备份数据只能康复到当时版别。所以假如你用户iOS 11下备份了数据,觉得不好用又刷回到iOS 10,这种状况iOS 11的备份数据是无法康复到iOS 10上的。所以在晋级iOS体系之前,应该在旧的体系下完整的经过iTunes备份数据,避免对新体系不满意挑选降级后无法康复本来的手机数据。
2、假如需求降级,应承认设备对应的体系固件。苹果设备的固件往往有不同的版别,尤其是前期的iPhone 5s等手机,可能有双网通和全网通之分,假如刷错固件轻则丢掉基带无法接打电话,严峻的还会导致手机无法开机。
对于苹果只能升级而不能降级你有什么看法呢,欢迎关注和评论区讨论
为什么苹果手机只能升不能降,我也经常想这个问题,后来我发现苹果为什么会成为世界第一的公司了,当你已成为习惯,这个习惯就很难改变,所以价值就会从中产生,这样的价值是难以估量的,造就了1.4万亿美元的神话。
人不可年年青春ios走的是要更新换代之路…一连数据无线网络就更新最新操作系统…
历史车轮向前进…是不允许倒退…旧设备上的糸统的漏洞对网络不利…因而网络商也大力推荐更新…腾讯大力推送与支持关系国外用户没有强行逼更新…
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