Many content users with the latest available versions of the iOS 9 jailbreak, although its functionality was quite limited when using Cydia with it. Moreover, if you have installed and have been trying to buy tweaks these days, you will have seen for yourself that was not possible. It was not an error on the version, or that something had gone wrong in the process.
Actually, all responding to alleged security reasons you quickly detail and now are being repealed.
Compatible Cydia tweaks with iOS 9 jailbreak could not be purchased directly because Jay Freeman had eliminated that possibility. The reason argued is that the latest versions of the jailbreak was not as stable as to have full access and, therefore, users saw as all that they had earlier in the terminal was inaccessible to them. From now, you can already access the applications market regularly.
Therefore, you will be able to buy all the tools that you find useful, as well as update tweaks that will be adapted to the new version without major problems.
The truth is that there have been too many complaints because of earlier problems with the jailbreak have justified a decision, so we have seen, it is not long maintained. Therefore, if until now only had been able to test some of the new iOS 9 jailbreak updating tweaks the already you arranged, but are willing to go further and to try all those who already have new version for the latest updates, you just have to stop by Cydia again.